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

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  • 1
    WinMerge

    WinMerge

    Windows visual diff and merge for files and directories

    WinMerge is a Windows tool for visual difference display and merging, for both files and directories. It is highly useful for determining what has changed between file versions, and then merging those changes. WinMerge has Unicode support, Flexible syntax coloring editor, Visual SourceSafe integration, and Windows Shell integration. Regexp filtering for filenames and lines. Side-by-side line difference and highlights differences inside lines. A file map shows the overall file differences in a location pane. The user interface is translated into several languages.
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    Downloads: 31,277 This Week
    Last Update:
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  • 2
    UltraDefrag

    UltraDefrag

    Increase your system performance with this easy to use tool

    Please note, here you can find the latest open source release of UltraDefrag (7.1.4). The most recent UltraDefrag release (15.0.0) can be found on our official website: https://ultradefrag.net UltraDefrag is a disk defragmenter for Windows, which supports defragmentation of locked system files by running during the boot process. It is easy to use without any complicated scripting or a huge load of configuration settings. You can filter the files processed by size, number of fragments, file name and path. You can terminate the process early by specifying an execution time limit.
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    Downloads: 1,201 This Week
    Last Update:
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  • 3
    Startup Manager is a program that provides you the possibility to manage the Windows startup procedure. It offers you the possibility to control which programs automatically start up and more.
    Downloads: 149 This Week
    Last Update:
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  • 4
    xpy
    xpy is a small software, securing your Windows 2000/XP/2003 installation and protecting your privacy. In addition to so-called Antispy features, it disables common security threats (RPC/DCOM, LMHash) and increases your Windows performance.
    Downloads: 10 This Week
    Last Update:
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  • 5
    ZK - Simply Ajax and Mobile
    ZK is an open-source Java framework for building modern web and mobile applications. It enables developers to create rich, interactive UIs using only Java — no JavaScript required. With 200+ Ajax-powered components, event-driven architecture, and support for popular technologies like Spring, Java EE, and JSP/JSF, ZK makes it simple to deliver powerful and user-friendly web applications.
    Downloads: 6 This Week
    Last Update:
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  • 6
    THIS PROJECT HAS BEEN ABANDONED SINCE 2007, NO SUPPORT WILL BE PROVIDED. Winpooch is a watchdog for Windows (2000, XP, 2003, but only 32-bits). It detects modifications in your system, so as to detect a trojan or a spyware installation. It also includes a real-time anti-virus. Set your own security level for anti-spyware, ant
    Downloads: 4 This Week
    Last Update:
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  • 7
    CyBerFuN xBTiT
    CyBerFuN xBTiT by cybernet2u / I only install hacks and maintain them / all the credits for the core source goes to : http://www.btiteam.org new files here ->https://github.com/cybyd/cybyd
    Downloads: 0 This Week
    Last Update:
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  • 8
    RunAsAdmin Explorer Shim is a tool that lets administrators to keep and easily use their administrative rights but still enjoy safety of using least privileged accounts.
    Downloads: 0 This Week
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  • 9
    Wake On Lan

    Wake On Lan

    A powerful WOL, ping, shutdown, GUI application.

    ATTENTION!!! Wol is now hosted on our own servers at http://wol.aquilatech.com. Wake On LAN, WakeOnLAN, shutdown software for Windows. A powerful WOL, ping, shutdown, GUI application.
    Downloads: 0 This Week
    Last Update:
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