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    The .NET Framework provides a comprehensive and consistent programming model for building applications that have visually stunning user experiences with seamless and secure communication.
    Describes how to troubleshoot error code 0x80070643 or error code 0x643 when updates are installed for the .NET Framework by using Windows Update or Microsoft Update or when you update Microsoft Security Essentials.
    Learn how to install earlier versions of .NET Framework on Windows 8, including version 3.5
    Describes the availability of an update for the .NET Framework 3.5 Service Pack 1.
    Describes a problem in which you receive an 0x800F0906, 0x800F081F, or 0x800F0907 error code when you try to install the .NET Framework 3.5 in Windows 8.1, Windows Server 2012 R2, Windows 8, or Windows Server 2012. Provides methods to resolve this problem.
    You may need to repair your installation of the .NET Framework if you upgrade your operating system or if the current installation of the .NET Framework becomes corrupted. This article describes how to do so. Steps to repair the .NET Framework...

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