Microsoft Knowledge Base:
971187(http://support.microsoft.com/kb/971187/ ) How to fix MSI software update registration corruption issues
To fix this problem automatically, click the Fix it button or link in the 971187 article.
Then visit the Windows Update Web site and try to install the updates:
If the problem is not resolved, proceed to Method 2.
Method 2: Repair the .NET Framework
To do this, follow these steps:
Click the following link to download the .NET Framework Cleanup Tool:
Use the .NET Framework Cleanup Tool to uninstall the .NET Framework versions 1.0, 1.1, 2.0, 3.0, and 3.5
Note The cleanup tool does not let you remove the .NET Framework 2.0 in Windows Vista or later versions because the .NET Framework is installed as an operating system component.
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