Browse free open source Calendar software and projects for Windows below. Use the toggles on the left to filter open source Calendar software by OS, license, language, programming language, and project status.

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  • 1
    Group Office groupware and CRM

    Group Office groupware and CRM

    Take your office and CRM into the cloud!

    Installation instructions can be found here: https://groupoffice.readthedocs.io/en/latest/install/install.html Group Office is an open source groupware application. It makes your daily office tasks easier. Share projects, calendars, files and e-mail online. It is a complete solution for all your online office needs. From a customer phone call to a project and finally an invoice. The support system helps to keep your customers happy. Group Office is fast, secure and has privacy by design. You can stay in full control of your data by self hosting your cloud and e-mail. Our document editing solution keeps all data on the secured server instead of synchronising it to all user devices. GroupOffice is open source and modular. Which means it’s easy to customise and extend. You can turn off and on features and it enables any developer to create new modules for the platform.
    Downloads: 101 This Week
    Last Update:
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  • 2
    WebCalendar
    Project has moved to github: https://github.com/craigk5n/webcalendar WebCalendar is a PHP application used to maintain a calendar for a single user or an intranet group of users. It can also be configured as an event calendar.
    Downloads: 11 This Week
    Last Update:
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  • 3
    HolyServices

    HolyServices

    Planning calendar for holy services

    A planning calendar for scheduling holy services at small parishes. Synchronizes with GoogleCalendar so as to be able to collaborate with mobile devices.
    Downloads: 58 This Week
    Last Update:
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  • 4
    Lifeograph

    Lifeograph

    Advanced personal note taking application

    Lifeograph is a diary program to take personal notes on life. It has all essential functionality expected in a diary program and strives to have a clean and streamlined user interface.
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    Downloads: 29 This Week
    Last Update:
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  • 5
    openCRX - Enterprise Class CRM

    openCRX - Enterprise Class CRM

    professional CRM and groupware service, ready for the cloud

    openCRX moved to https://github.com/opencrx
    Downloads: 4 This Week
    Last Update:
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  • 6
    RemoteCalendars is a COM-.NET Add-in for Outlook 2003/2007, written in C#. After installing this plugin, every Outlook user should be able to subscribe, reload and delete a generic remote iCalendar (RFC 2445) from Outlook 2003/2007.
    Downloads: 1 This Week
    Last Update:
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  • 7
    BMCS is an ultimate easy-to-use tool, which helps to look about the correct nutrition and diet. Easy operational and user-friendly GUI guarantees efficient usage. Do you want to be fit, healthy and not to get overweight? Then use BMCS!
    Downloads: 0 This Week
    Last Update:
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  • 8
    BRIM is a MVC framework, written in PHP and based on items with a hierarchical relationship. The list of plugins make BRIM a Information Manager with plugins like bookmarks, a calendar, contacts tasks, notes, RSS etc. The application is multilingual.
    Downloads: 0 This Week
    Last Update:
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  • 9
    minthcm

    minthcm

    Free, open-source Human Capital Management system

    minthcm.org is a free and open-source tool for Human Capital Management. Mint based on two popular, well-known business applications: SugarCRM Community Edition and SuiteCRM. This is why we often say that MintHCM is CRM reinvented. You all know how much goes into technological development of this type of business software… That's why we need your help. Thanks to the open code of both SugarCRM CE and SuiteCRM we were able to reintroduce some features, redesign other, and provide brand new system to the users. The code of MintHCM remains open so feel free to use it.
    Downloads: 0 This Week
    Last Update:
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  • 10
    NETOFFICE EIS: CRM/SRM Corporate AddressBook ; iCAL Corporate Calendar + Agenda ; eMSG MailBox Email + Fax Messagery ; DMS FileManager + Document Management ; EXTM ModExpress (modules / extra apps: financial, sales) ; CPanel administration ; Intercha
    Downloads: 0 This Week
    Last Update:
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