Alternatives to Zentyal
Compare Zentyal alternatives for your business or organization using the curated list below. SourceForge ranks the best alternatives to Zentyal in 2026. Compare features, ratings, user reviews, pricing, and more from Zentyal competitors and alternatives in order to make an informed decision for your business.
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Greatmail
Greatmail
Dependable cloud based email hosting with spam filtering, antivirus protection, generous storage and webmail. Compatible with Outlook and all other POP3/IMAP clients. High volume SMTP service for responsible senders. Outbound relay service for transactional messages, email marketing campaigns, newsletters and other applications. Dedicated email servers, clustering and multiple IP load balancing for high volume senders. Fixed monthly cost with unlimited sending and reputation monitoring. Greatmail is an email service provider (ESP) specializing in business class email hosting, SMTP hosting and email servers. For ISPs, application programmers and cloud developers, we also provide custom solutions including dedicated IP servers and process specific, load balanced configurations with multiple servers. -
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FreeIPA
FreeIPA
Manage Linux users and client hosts in your realm from one central location with CLI, Web UI or RPC access. Enable Single Sign On authentication for all your systems, services and applications. Define Kerberos authentication and authorization policies for your identities. Control services like DNS, SUDO, SELinux or autofs. Integrated security information management solution combining Linux (Fedora), 389 Directory Server, MIT Kerberos, NTP, DNS, Dogtag certificate system, SSSD and others. Built on top of well-known Open Source components and standard protocols. FreeIPA is an integrated security information management solution combining Linux (Fedora), 389 Directory Server, MIT Kerberos, NTP, DNS, Dogtag (Certificate System). It consists of a web interface and command-line administration tools. -
3
MailEnable
MailEnable
MailEnable provides an end to end solution for providing secure email and collaboration services. A recent independent survey reports MailEnable as the most popular Windows Mail Server Platform in the world. Whether you are a hosting company providing email services to thousands of end users or a small business with a single domain, MailEnable provides a solution that will impress your mail users. MailEnable provides Windows Mail Server software with features comparable to Microsoft Exchange. It provides powerful messaging services like Exchange ActiveSync, IMAP, SMTP, POP3 and collaboration tools such as calendaring (CalDAV), contacts (CardDAV), tasks and notes.Starting Price: $349 -
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hMailServer
hMailServer
hMailServer is a free, open source, e-mail server for Microsoft Windows. It's used by Internet service providers, companies, governments, schools and enthusiasts in all parts of the world. It supports the common e-mail protocols (IMAP, SMTP and POP3) and can easily be integrated with many existing web mail systems. It has flexible score-based spam protection and can attach to your virus scanner to scan all incoming and outgoing email.Starting Price: Free -
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Mailu
Mailu
Mailu is a simple yet full-featured mail server as a set of Docker images. It is free software (both as in free beer & as in free speech), open to suggestions and external contributions. The project aims at providing people with an easily setup, easily maintained and full-featured mail server while not shipping proprietary software nor unrelated features often found in popular groupware. Main features include: Standard email server, IMAP and IMAP+, SMTP and Submission with autoconfiguration profiles for clients Advanced email features, aliases, domain aliases, custom routing Web access, multiple Webmails and administration interface User features, aliases, auto-reply, auto-forward, fetched accounts Admin features, global admins, announcements, per-domain delegation, quotas Security, enforced TLS, DANE, MTA-STS, Letsencrypt!, outgoing DKIM, anti-virus scanner, Snuffleupagus, block malicious attachments Antispam, auto-learn, greylisting, DMARC& SPF, anti-spoofingStarting Price: Free -
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Courier
Double Precision, Inc.
The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list services within a single, consistent, framework. Individual components can be enabled or disabled at will. The Courier mail server now implements basic web-based calendaring and scheduling services integrated in the webmail module. Advanced groupware calendaring services will follow soon. The Courier mail server's source code should compile on most POSIX-based operating systems based on Linux, and BSD-derived kernels. The Courier mail server should also compile on Solaris and AIX, with some help from Sun's or IBM's freeware add-on tools for their respective operating systems. The Courier mail server evolved out of several related projects, that merged together (more on that later). The Courier mail server implements SMTP extensions for mailing list management.Starting Price: Free -
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MDaemon Email Server
MDaemon Technologies
The MDaemon Email Server was one of the first Microsoft Exchange alternatives offered to businesses around the world. It has been developed with the ongoing input from IT professionals seeking an easy-to-use, reliable, and secure mail server that does not require expensive administration or impose high per-user costs. It simplifies messaging and collaboration with a focus on security and privacy, an intuitive, user-friendly web mail design and by offering administrators Mobile Device Management, Business Instant Messaging, Document Sharing, and other enterprise-class features that can be managed with minimal support. MDaemon Email Server supports IMAP, SMTP, and POP3 protocols, and features include: integrated webmail with IM and document sharing, Outlook support, compromised password alerts, color-coded log files for quick and easy troubleshooting, customizable email policy setting to fit your unique network environment, Mobile Device Management, Account Hijack Detection, and more.Starting Price: $360 per year -
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Mail-in-a-Box
Mail-in-a-Box
Mail-in-a-Box lets you become your own mail service provider in a few easy steps. It’s sort of like making your own gmail, but one you control from top to bottom. Technically, Mail-in-a-Box turns a fresh cloud computer into a working mail server. But you don’t need to be a technology expert to set it up. Each Mail-in-a-Box provides webmail and an IMAP/SMTP server for use with mobile devices and desktop mail software. It also includes contacts and calendar synchronization. The box also includes other standard mail functionality like spam protection (spam filtering and greylisting), mail filter rules, email client autoconfiguration, and automated backups to Amazon S3 and other services. The box also includes automatic DNS configuration when you let it become your nameserver so that it can set important DNS records for mail deliverability and security including SPF, DKIM, DMARC, and MTA-STS. When enabled, DNSSEC (with DANE TLSA) provides a higher level of protection.Starting Price: Free -
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Hexamail POP3 Downloader
Hexamail
POP3 Downloader is a high-performance, scalable, real-time POP3 connector for your mail server. It supports downloading and forwarding any POP3 or IMAP account email to any email server that supports SMTP or IMAP. Key Features: 100% Compatibility with all versions of Exchange 100% Compatibility with all SMTP servers End-user management via a web interface Antivirus and Antispam options IMAP Support (with folders) IMAP Push Support Gmail Support 1-minute scheduling No email size limits Microsoft Exchange integration without the need for a public SMTP server or static IP address Migrate or integrate unlimited external POP3 or IMAP email accounts into local mailboxes Continue receiving mail from legacy accounts during migration to a new mail server IMAP migration or IMAP sync between two IMAP servers Reliable, easy to install, and cost-effective solution Streamline your email integration processes and automate email downloads with Hexamail POP3 Downloader.Starting Price: $114/10 users -
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Microsoft SMTP Service
Microsoft
Microsoft SMTP Service is a mail server software that enables Microsoft Windows Server operating systems to send and receive emails. It is a component of Internet Information Services (IIS) and is used to relay emails between mail servers. Microsoft SMTP Service is a popular choice for organizations that need a reliable and scalable mail server solution. It is easy to install and configure and can be used with a variety of email clients. Microsoft SMTP Service supports a number of features, including: Relaying emails between mail servers: Microsoft SMTP Service can relay emails between mail servers, which means that it can be used to send and receive emails for multiple domains. Supporting multiple email clients: Microsoft SMTP Service can be used with a variety of email clients, including Microsoft Outlook, Mozilla Thunderbird, and Apple Mail. Providing security features: Microsoft SMTP Service provides a number of security features, such as authentication and encryption -
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Xeams
Synametrics Technologies
Xeams is, a secure and powerful complete mail server for Windows, Linux, Solaris, MacOSX and other flavors of UNIX. Xeams supports SMTP, POP3, and IMAP. It features a powerful spam filtering engine that eliminates up to 99% of junk email upon installation. The software offers a flexible approach to email, making it a very user-friendly server. Xeams can block 99% percent of all junk messages right out of the box. The filtering rules are fully customizable and get better as Xeams adapts to your email environment. IMAP and POP3 servers built right into the system to easily fetch emails from an email repository to a client's machine. Xeams can be used as an email firewall in front of another server, such as MS Exchange, or as a full email server requiring no other software to process emails. Use Xeams in front of your Office 365 infrastructure to gain additional filtering, reporting and archiving capabilities that you don't get with Office 365 alone.Starting Price: $20.00/year/user -
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MailSite Fusion
Rockliffe Systems
MailSite Fusion is a Windows email, calendar and contact server with over-the-air push to all types of smartphones, Full native Outlook sync, a sophisticated AJAX web client and a calendar and contact sharing server, which can synchronize and publish to many other clients. MailSite has been voted in the top 3 mail server products by readers of Windows IT Pro Magazine 3 years running. Your email services are critical to your organization. So you need to be sure that you select a quality product, from a company with a proven track record in communication software. So, why this mail server? Because Rockliffe understands your concerns, we have been specializing in developing and refining our email server and email security software for business and service providers since 1995. Built from the ground up to be fast, stable and secure, MailSite Fusion is ready to meet the needs and requirements that matter to you most.Starting Price: $90 per year -
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Dovecot Pro
Open-Xchange
Dovecot Pro is a full-service email platform that delivers dynamic scalability, high performance, efficient utilization of hardware, and outstanding support to the world’s largest Telcos, ISP's, and Hosters. With a marketshare of 76% of installed email backends, customers trust the performance of Dovecot Pro. Efficient hardware utilization and advanced monitoring tools for statistics and administration reduce ownership costs and save time and maintenance costs. In addition, Dovecot Pro scales up and out to hundreds of servers and millions of users and multiple physical sites. Its stateless native architecture offers maximum flexibility as each major component can be deployed on its own dedicated node. Dovecot Pro provides industry-leading support for all email standards necessary to provide both Mail Delivery Agent functionality (via LMTP and Sieve), and to facilitate mail retrieval by mail clients (via IMAP and POP3). -
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Dovecot
Dovecot
Dovecot is an excellent choice for both small and large installations. Dovecot is among the best performing IMAP servers while still supporting the standard mbox and Maildir formats. The mailboxes are transparently indexed, which gives Dovecot its good performance while still providing full compatibility with existing mailbox handling tools. Dovecot is standards compliant. Dovecot passes all IMAP server standard compliancy tests while most other servers fail many of them. Dovecot’s indexes are self-optimizing. They contain exactly what the user’s client commonly needs, no more and no less. Dovecot is self-healing. It tries to fix most of the problems it notices by itself, such as broken index files. The problems are however logged so the administrator can later try to figure out what caused them. Dovecot tries to be admin-friendly. Common error messages are made as easily understandable as possible.Starting Price: Free -
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OpenSMTPD
OpenSMTPD
OpenSMTPD is a free implementation of the server-side SMTP protocol as defined by RFC 5321, with some additional standard extensions. It allows ordinary machines to exchange emails with other systems speaking the SMTP protocol. Started out of dissatisfaction with other implementations, OpenSMTPD is a fairly complete SMTP implementation. OpenSMTPD is primarily developed by Gilles Chehade and Eric Faurot, with contributions from various OpenBSD hackers and members from other communities.Starting Price: Free -
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Haraka
Haraka
Haraka can serve thousands of concurrent connections and deliver thousands of messages per second. Haraka and plugins are written in asynchronous JS and are very fast. Haraka has very good spam protection (see plugins) and works well as a filtering MTA. It also works well as an MSA running on port 587 with auth and dkim_sign plugins enabled. Haraka makes no attempt to be a mail store (like an exchange or postfix/exim/qmail), an LDA, or an IMAP server (like Dovecot or courier). Haraka is typically used with such systems. Haraka has a scalable outbound mail delivery engine built in. Mail marked as relaying (such as via an auth plugin) is automatically queued for outbound delivery. Haraka's plugin architecture provides an easily extensible MTA that complements traditional MTAs that excel at managing mail stores but do not have sufficient filtering.Starting Price: Free -
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Horde
Horde
Horde is the most flexible groupware on the planet, and that makes it the perfect platform on which to build your business productivity software. Horde connects to (and officially supports) more backends (all the leading SQL, LDAP, IMAP, Sieve, SMTP, cache platforms available today) than any other open source groupware system. This means you can continue to use your existing userbase and your users do not have to remember any additional passwords. Horde's feature set rivals the largest enterprise email systems. We have an incredible feature set that compares favorably against any competition in our primary apps (mail, calendar, address book), and even more in our secondary apps (time tracking, wiki, ticketing, and more).Starting Price: Free -
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Eudora Internet Mail Server
Eudora Internet Mail Server
Completely rewritten relay restrictions with an easier to use interface that gives finer control over relay security. New domain name resolver (DNR), EIMS now has it's own DNR, which works around bugs in the Open Transport DNR and performance problems with the OS X DNR. The new DNR does not currently support non-recursive DNSs. SMTP Submit port, this is a second SMTP port running on TCP port 587 by default. It currently works exactly the same as the standard SMTP port. This is handy for clients that are stuck behind an ISP that blocks port 25 access. Sending Setup option for maximum recipients per message. Expand SMTP Addresses option, you can now turn this off, with EIMS 3.1 and earlier it was always on. The SMTP server (both port 25 and 587) now reports Telnet connections and connections that look like port scans (connections where no data is sent and it doesn't time out).Starting Price: Free -
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SmarterMail
SmarterTools
SmarterMail is the ideal Microsoft Exchange alternative. It’s the only business email server on the market that offers native support for Exchange protocols: MAPI, EWS, and EAS, without requiring any additional software or plug-ins for Microsoft Outlook or other desktop or mobile clients. It delivers all the features of Exchange at a fraction of the cost. SmarterMail also includes audio/video group chat and Online Meetings for team collaboration at no extra charge. Its newest feature, the SmarterMail Marketplace, enables seamless integration with platforms like OnlyOffice, Collabora, and AI tools such as OpenAI’s ChatGPT. Available for both Windows and Linux, SmarterMail has lower hardware requirements, superior stability, and reduced maintenance costs. It’s the perfect solution for businesses of any size or industry seeking Exchange-level functionality, without the high costs.Starting Price: $500.00/one-time -
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Bit SMTP
Bit Apps
Many site owners face the spam mail problem for using the WordPress default PHP mail function. There may be some restrictions when it comes to mail service: sometimes emails are not delivered, sites cross the limit of outgoing mail. Bit SMTP plugin allows you to authenticate the mail service of your site by configuring the SMTP server of your desired mail service. SMTP is a protocol that helps your WordPress site make its email deliverability more easygoing & reliable. By enabling this feature, you can send mail from your site to your recipients via your preferred mail server. -
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RainLoop
RainLoop
Modest system requirements, decent performance, simple installation and upgrade, no database required - all these make RainLoop Webmail a perfect choice for your email solution. Modern user interface. Complete support of IMAP and SMTP protocols including SSL and STARTTLS. Sieve scripts (Filters and vacation message). Minimalistic resources requirements. Direct access to mail server is used (mails are not stored locally on web server). Allows for adding multiple accounts to primary one, simultaneous access to different accounts in different browser tabs is supported. Additional identities. Administrative panel for configuring main options. Really simple installation and update. Integration with Facebook, Google, Twitter and Dropbox. Managing folders list. Simple look'n'feel customization. Configurable multi-level caching system. Extending functionality with plugins installed through admin panel. Perfect rendering of complex HTML mails. Drag'n'drop for mails and attachments.Starting Price: $95 per year -
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Mercury Mail Transport System
Pegasus
Mail from the outside world is received by Mercury and placed in the addressee's mailbox, where the user can access it at any later point. Messages sent by local users to the outside world are passed to Mercury, which then takes whatever steps are necessary to deliver them, removing the burden from the user's workstation and allowing him to continue with other work. If you connect using a dialup connection, then only the mail server needs to be able to access that connection. Your workstations do not need their own modems or Internet accounts. The mail server can continue processing mail even when the client workstations are turned off, allowing functions that depend on a continuously available service, such as automatic replies and auto-forwarding. -
23
Afterlogic Aurora
AfterLogic
Groupware system for businesses and providers, backed with mobile apps. Your private cloud combining groupware, file storage and email in a single, unified environment. Clean and modern interface. Can work with your existing mail server or use its own for the complete solution. iOS/Android apps for Email and Files let your users just type their email/password and never deal with mail server settings or blocked IMAP/SMTP ports. Can be integrated with LDAP authentication or LDAP address book, along with OAuth 2.0 authentication and resources, like Google Drive or Dropbox.Starting Price: $99.00/one-time -
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Mutant Mail
Fresent
Never miss an important email again! Manage all your email IDs in one inbox with our Email Router. Struggling with multiple Emails? Overcome the headache of managing multiple Email ids with our privacy-focused, server-side solution Mutant Mail. Problem: Imagine having 5 domains, with 5 Email IDs each (admin, support, help, legal, contact). That's 25 Email IDs. Do we want to log in to every mailbox to keep the domain persona? Answer: Receive, Reply & Send all Emails for your Domains from your free Gmail account(or any Email account) and save on Email Hosting. Skip the Email client setup headache! Forget about Credentials, SMTP, IMAP/POP for every Email id with Mutant Mail. With Mutant Mail service you can receive, send and reply all using one mailbox. Spoof-proof your Emails with complimentary DMARC Report. PGP/GPG encryption. Buffer / Batch your emails.Starting Price: $2.99 per month -
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WebCrossing
Elliptics
WebCrossing Community gives you the parts you need to create an infinitely flexible online community. Create any structure you need, with dozens of plug-ins and applications available to customize and add functionality to your site. WebCrossing Core is a full-featured multi-domain web server including HTTP, SMTP, IMAP, XML-RPC, FTP, NNTP and more. User objects, folders, discussions and messages are all native features. The scriptable, integrated objected-oriented NoSQL database is what you are looking for if you need to handle complex data structures. Webcrossing Neighbors group tools include blogs, discussion forums, calendars, wikis, custom pages, file stores and more. Each group can have a custom landing page. Public, private and hidden groups are supported. Since all WebCrossing servers have a built-in mail server, your members can post by email or the web, so your online forums can also be used as interactive mailing lists with an online archive.Starting Price: $99.00/month -
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Modoboa
Modoboa
Regain your independence and protect your privacy by installing your own email server. It takes less than 10 minutes! Create your mail server for free in less than 10 minutes with Modoboa When it comes to create a mailbox, you generally have several solutions: - Use the services offered by Internet providers (Orange, Vodafone...) of infrastructure providers (OVH, Gandi...) with a monthly or annual subscription. However, customization and configuration possibilities, domains and mailboxes number are limited. - Use the services of free email providers (Gmail, Live, Yahoo...) which are limited and your data is used for commercial purposes. - Install your own email server, which requires important technical knowledge to setup and configure the system. Modoboa is an alternative to those 3 options. It frees you from dependence on email providers and makes accessible to all the creation his own secure email server. The whole thing, in less than 10 minutes and freely.Starting Price: Free -
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Trojitá
KDE
Trojitá is an email program ("client") specialized in giving fast and efficient access to mailboxes over the IMAP protocol. An IMAP mail server stores messages and allows clients to fetch messages to the local computer when asked for. It prioritizes efficiency, speed and open standards above other goals. Trojitá also aims to be multi-platform, and functions well on everything from big desktop computers to small cellphones. Trojitá is a stand-alone program, not part of a "personal information manager" suite. -
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iRedMail
iRedMail
The right way to build your mail server with open source softwares. Works on CentOS Stream, Rocky, Alma, Debian, Ubuntu, FreeBSD, OpenBSD. With iRedMail, you can deploy an OPEN SOURCE, FULLY FLEDGED, FULL-FEATURED mail server in several minutes, for free. We did the heavy lifting of putting all the open source components together and applying best practices. Our product does all the major tasks for you. Furthermore we offer professional support to back you up in case you have some problems. You have all personal data on your own hard disk, you can control the email security, inspect transaction log. No other organization can see the content of all messages. All components used in iRedMail are open source softwares, and you get the bug fixes and updates from the Linux/BSD venders you trust. iRedMail is the right way to build your mail server with open source softwares.Starting Price: Free -
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Amazon WorkMail
Amazon
Amazon WorkMail is a secure, managed business email and calendar service with support for existing desktop and mobile email client applications. Amazon WorkMail gives users the ability to seamlessly access their email, contacts, and calendars using the client application of their choice, including Microsoft Outlook, native iOS and Android email applications, any client application supporting the IMAP protocol, or directly through a web browser. You can integrate Amazon WorkMail with your existing corporate directory, use email journaling to meet compliance requirements, and control both the keys that encrypt your data and the location in which your data is stored. You can also set up interoperability with Microsoft Exchange Server, and programmatically manage users, groups, and resources using the Amazon WorkMail SDK. Amazon WorkMail features simple, low, monthly per-user pricing and costs $4 per user per month which includes 50GB of storage per user.Starting Price: $4 per user month -
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Cyrus IMAP
The Cyrus Team
Cyrus IMAP is an email, contacts and calendar server. Cyrus is free and open source. Features: Speed Security Efficiency Search CardDAV and CalDAV support Robust data storage Replication Scalable for large installations Flexible filtering support through Sieve Supports antivirus and antispam toolkits Handles deliverability: SPF, DKIM, DMARC Extensive authentication options, through Cyrus SASL JMAP support Long list of supported standardsStarting Price: Free -
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SpamCheetah
Gayatri Hitech
SpamCheetah is a very affordable and effective way to combat spam, malware and viruses at mail server level. It operates as an SMTP proxy and stops all kind of phishing and business email compromise at SMTP level. It uses a combination of network level techniques like greylisting, greytrapping, blacklisting, URL scanning, malware API checks and a lot more. It comes with standard email gateway features like sender and recipient based blocking, attachment size blocking, MIME type filtering and pattern based blocking alongside quarantine reports and mail metadata reports and much more. We offer trial for 30 days along with two editions, one for single mail server and one for multiple mail servers. We also offer ISO download, VMWare appliance and raw VM download options.Starting Price: $1/month/user -
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Apache James
The Apache Software Foundation
James stands for Java Apache Mail Enterprise Server. It has a modular architecture based on a rich set of modern and efficient components which provides at the end complete, stable, secure, and extendable Mail Servers running on the JVM. Create your own personal solution of email treatment by assembling the components you need thanks to the Inversion of Control mail platform offered and go further customizing filtering and routing rules using James Mailet Container. The Apache James project wires together the different libraries composing James to provide running services, ready to download on the Apache mirrors.Starting Price: Free -
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Atomic Email Verifier
AtomPark Software
Email validity check to improve deliverability. Remove nonexistent email addresses to increase email servers’ confidence to your messages. The program checks email addresses against standard spelling rules. Connect to the SMTP server and check the email address's existence on it. The domain is verified; in the case of an incorrect domain, the email address will not exist. Fast and easy mailing lists import from local files of different formats. Atomic Mail Verifier is a program that checks email addresses against standard spelling rules. Email address checker works in multi-thread mode, which allows you to check email address validity even faster. Our email checker software performs validation step by step. The program is designed to import an email, check it's syntax first, then its domain name and afterward send a query to the corresponding email server. Effective management of email lists for creating a perfect contact base.Starting Price: $69.85 one-time payment -
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H-Sphere
Positive Software
H-Sphere is a scalable multiserver web hosting solution. It has many advanced features and a sophisticated billing system to automate and improve your web hosting tasks. H-Sphere was designed to work on many servers and can be scaled by adding more web, mail, database, and DNS servers without any downtime. It provides a simple, easy-to-use web interface that can be maintained from any computer with an internet connection. H-Sphere was written in Java and works with any SQL-compliant database. It runs only industry-standard software. H-Sphere follows a true centralized model to allow the highest level of manageability. The data is stored in the centralized database. Control panel server dispatches command (using ssh or http protocols) to different servers. New servers can be added on the fly. The control panel server manages all new machines, users, domains, and events behind the scene.Starting Price: $4.50 one-time payment -
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MailHog
MailHog
Inspired by MailCatcher, easier to install. MailHog is an email testing tool for developers: Configure your application to use MailHog for SMTP delivery. View messages in the web UI, or retrieve them with the JSON API. Optionally release messages to real SMTP servers for delivery. See MailHog libraries for a list of MailHog client libraries. ESMTP server implementing RFC5321. Support for SMTP AUTH (RFC4954) and PIPELINING (RFC2920). Web interface to view messages (plain text, HTML or source). Supports RFC2047 encoded headers. Real-time updates using EventSource. Release messages to real SMTP servers. Chaos Monkey for failure testing. See Introduction to Jim for more information. HTTP API to list, retrieve and delete messages. See APIv1 and APIv2 documentation for more information. HTTP basic authentication for MailHog UI and API. Multipart MIME support. Download individual MIME parts. In-memory message storage. MongoDB and file-based storage for message persistence. -
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SquirrelMail
SquirrelMail
SquirrelMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript required) for maximum compatibility across browsers. It has very few requirements and is very easy to configure and install. SquirrelMail has all the functionality you would want from an email client, including strong MIME support, address books, and folder manipulation. The need arose in our organization for the access of email and address books from anywhere in the world. Obviously a web interface is ideal for this, given that the user has access to the Internet. After reviewing several open source projects we realized that we were going to need to do some fairly major customizations to get things to be a nice fit for our needs. -
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Kopano
Kopano
We provide you with your digitally sovereign solution to keep track of your e-mails and calendars, to organize yourself with tasks or to stay in contact with team colleagues via video meeting. Kopano Groupware is an e-mail and calendaring solution, which can be operated digitally sovereign. Its functionality is comparable to that of Microsoft Outlook and Exchange. Kopano Groupware installations can be operated with more than 100,000 users. Kopano Groupware is an e-mail and calendar server that provides users with their daily communication and organizational data on all devices and connects teams. Data can be jointly edited in public folders or shared with others from your own inbox.Starting Price: $17 per year -
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eSoftTools IMAP Backup & Migration Software
eSoftTools Software
eSoftTools IMAP Backup and Migration Software is a professionally advanced and powerful IMAP email backup tool that helps users securely back up, download, or migrate emails from any IMAP-supported account. With its simple graphical interface, it becomes a user-friendly application to adopt and use for IMAP email backup and migration in more than 15+ file formats and popular cloud email platforms like Office 365, Gmail, Google Workspace, Yahoo Mail, and other IMAP server accounts. This tool is proudly supports all major IMAP servers for email backup, including Gmail, Google Workspace, Yahoo Mail, Outlook.com, Office 365, AOL, Zoho Mail, GoDaddy, Hostinger, HostMonster, iPage, BlueHost, MochaHost, and all other hosting-provided company email systems. The software is fully capable to download entire mailbox or any specific date range of emails with fast scanning and secure process. Users can export emails including Outlook PST, EML, EMLX, MSG, MBOX, Lotus Notes NSF, HTML, and more.Starting Price: $99 -
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Server Check
FearWorks Media Ltd.
The Server Check Monitoring System continually monitors your websites and other internet-based services (Ping, SMTP, IMAP, FTP, etc.) and makes sure you're the first to know when there's an outage. Don't lose any more visitors to downtime. Our FREE 10-monitor version of Server Check lets you get started with monitoring in less than five minutes completely free! Get alerted as soon as something stops working: visual alerts, audible alarms, emails and SMS texts to as many admins as you need. Server Check makes sure you know about it so you can fix it! Quick setup of all common protocols, including HTTP & HTTPS, Ping, FTP, SMTP, POP3, IMAP, TCP, MySQL. Monitor them all and stay ahead of any long outages that might lose customers! View statistics for each monitor, response time graphs, outage length reports, web-based stats and uptime pages, and keep track of uptime and downtime over the last 12 months.Starting Price: Free -
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MailInput
Devro LABS
This email verification tool actually connects to the mail server and checks whether the mailbox exists or not, wiping out disposable email addresses from your email list. This email verification tool actually connects to the mail server and checks whether the mailbox exists or not. Email Checker is a simple tool for verifying an email address. It's free and quite easy to use. Just enter the email address and hit the verify button. Then it tells you whether the email address is real or not. It extracts the MX records from the email address and connects to the mail server (over SMTP and also simulates sending a message) to make sure the mailbox really exists for that user/address. As it uses our unique set of data, the Email Verifier can return a result even where other standard verification tools fail. Our validation process has multiple threads, email format, domain information, server status, and email type.Starting Price: Free -
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SOGo
SOGo
SOGo is a fully supported and trusted groupware server with a focus on scalability and open standards. SOGo is released under the GNU GPL/LGPL v2 and above. SOGo provides a rich AJAX-based Web interface and supports multiple native clients through the use of standard protocols such as CalDAV, CardDAV and GroupDAV, as well as Microsoft ActiveSync. SOGo is the missing component of your infrastructure; it sits in the middle of your servers to offer your users a uniform and complete interface to access their information. It has been deployed in production environments where thousands of users are involved. -
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Apache Synapse
Apache Software Foundation
Apache Synapse is a lightweight and high-performance Enterprise Service Bus (ESB). Powered by a fast and asynchronous mediation engine, Apache Synapse provides exceptional support for XML, Web Services and REST. In addition to XML and SOAP, Apache Synapse supports several other content interchange formats, such as plain text, binary, Hessian and JSON. The wide range of transport adapters available for Synapse, enables it to communicate over many application and transport layer protocols. As of now, Apache Synapse supports HTTP/S, Mail (POP3, IMAP, SMTP), JMS, TCP, UDP, VFS, SMS, XMPP and FIX. High-performing PassThrough HTTP transport support for all mediation scenarios. Ultra-fast, low latency mediation of HTTP requests. Supporting a very large number of inbound (client -> ESB) and outbound (ESB -> server) connections concurrently. Intelligently handle message content and content awareness built into the engine with shared buffer for handling data. -
43
AdRestore
Microsoft
Windows Server 2003 introduces the ability to restore deleted ("tombstoned") objects. This simple command-line utility enumerates the deleted objects in a domain and gives you the option of restoring each one. Source code is based on sample code in the Microsoft Platform SDK. ADInsight is an LDAP (Light-weight Directory Access Protocol) real-time monitoring tool aimed at troubleshooting Active Directory client applications. Use its detailed tracing of Active Directory client-server communications to solve Windows authentication, Exchange, DNS, and other problems. ADInsight uses DLL injection techniques to intercept calls that applications make in the Wldap32.dll library, which is the standard library underlying Active Directory APIs such ldap and ADSI. Unlike network monitoring tools, ADInsight intercepts and interprets all client-side APIs, including those that do not result in transmission to a server. -
44
ProDMARC
PROGIST
Attackers use spoofed emails to phish your customer’s & employee’s credentials. Hackers send forged invoices through mails to your partners & suppliers. Attackers send malicious mails containing malware like Ransomware. Attackers sell illegal goods like weapons or drugs using mail by spoofing trusted brands. DMARC is an email validation protocol built on 2 globally accepted authentication protocols namely SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail). SPF is an email authentication protocol that allows the receiving mail server to check if the sender mail server is authorized to send emails on behalf of the organization. DKIM is a public and private cryptography based authentication protocol designed to ensure that messages aren’t altered in transit between the sender & receiver mail server.Starting Price: $100 per year -
45
Oracle Communications Messaging Server is a standards-based Internet messaging server designed for high-capacity, reliable message handling for service providers and their customers. Messaging Server provides support for several email protocols and can manage embedded text, sound, graphics, video files, and other files and formats.
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46
Mailtraq
Mailtraq
Mailtraq Professional mail server software is the complete email server for business. It does everything you need at a great price and without hassles. Mailtraq is the ideal Microsoft Exchange Alternative: easy to deploy and simple to manage. Low license cost, no server-CALs, and stability in operation make Mailtraq email server software the choice for all SMB and SOHO businesses. Email is at the heart of your company or organization, and where those messages are stored is of vital importance to the long-term health of your firm. There is a degree of hassle and expense involved in running your own email server but it gives you complete physical control over who has access to your email. If you use your ISP's service then their system administrators can see and read your messages. Similarly, if you use a SAAS supplier for a hosted email service, and if you use a Cloud provider you not only don't know who is reading your email, but don't even know where in the world it is kept. -
47
SyncBackPro
2BrightSparks
SyncBackPro is an advanced file backup and synchronization program that can be used with hard drives, removable media (e.g. USB drives), FTP, FTPS, and SFTP servers, Zip64 archives (with 256-bit AES encryption), POP3/IMAP4/SMTP email servers, Media Transfer Protocol devices, network shares, and cloud storage services (S3, Azure, Dropbox, OneDrive, Google Drive, Box, and many others). Highly configurable, SyncBackPro includes: open/locked file copying; file versioning; scripting; fast backup; true synchronization; Zip64 support; compression filtering; detailed and easy to read log files; email results; simulated backups and restore; file filters; sub-directory selection; copy verification; background backups; auto-close of programs; profile groups; compare files, and an extensive context sensitive help file.Starting Price: $54.95/one-time/user -
48
WinGate
WinGate
WinGate Proxy Server is a highly capable HTTP Proxy server, SOCKS server, integrated Internet gateway and communications server designed to meet the access control, security and communications needs of today's businesses. In addition to a comprehensive range of features, WinGate Proxy Server's license options provide you the flexibility to match your needs to your budget, whether you need to manage an enterprise, small business, or home network. WinGate Proxy Server will share most types of Internet connection, allowing multiple users to simultaneously surf the web, retrieve their email, or use other internet programs, as if they were directly connected to the Internet. Whether it is a simple dialup modem or high speed fibre, WinGate Proxy Server can help to make the most out of the connection. WinGate Proxy Server supports a wide variety of Internet protocols, allowing applications such as Web browsers, messaging software, FTP and SSL.Starting Price: $109.95 one-time payment -
49
OpenText Core Email Continuity
OpenText
The OpenText Core Email Continuity solution ensures continuous access to email even when your primary mail infrastructure goes down, by automatically redirecting messaging to a secure web portal or Outlook via POP/IMAP, allowing users to read, reply, forward, compose, and send email normally during outages. It provides up to 30 days of stored inbound messages, preserving recent email history. During a mail-server outage, incoming messages are spooled at the spam filter, and users are automatically directed to the continuity service; once the primary server returns online, all email activity (sent items, replies, forwards, new messages) syncs back automatically to the main mailbox, preserving continuity. It requires no additional hardware, it auto-provisions through a central portal, and runs transparently until needed. Access can be from any device, anywhere, via web or standard email clients. -
50
Poste.io
analogic
You can have a fully functional mail server installed in a few minutes, mostly waiting for scripts to do the work. The whole package is designed with reasonable defaults to get you up and running quickly, without having to know the internals and without making decisions that could break the email system. User data and configuration is strictly separated from binaries. User database is stored in SQLite database - in file. This makes Poste.io fully compatible with external storage. Migration, backups or updates are therefore very easy and mostly consist of files manipulation. Poste.io has been built from the ground up with security in mind. Internet history is littered with painful security incidents, so we traded old email client compatibility and insecure authentication methods for features that meet today's for features that meet modern security requirements.Starting Price: Free
