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    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.
    The .NET Framework is an integral part of many applications running on Windows and provides common functionality for those applications to run. For developers, the .NET Framework provides a consistent programming model for building applications.
    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...
    Describes steps that you can follow to repair installation issues in the.NET Framework 2.0.

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