If you try to run the installer and it fails or tells you it is already installed, you likely have a corrupted version. Here is the proper fix procedure for Windows 7:
Rename the folder C:\Windows\SoftwareDistribution to SoftwareDistribution.old . Download Net Framework 4.0.3019 For Windows 7 64 11 Fix
The .NET Framework is a software framework developed by Microsoft that runs primarily on Microsoft Windows. Version is the specific build number for .NET Framework 4.0. It includes the Common Language Runtime (CLR) and the class libraries required to execute code for thousands of legacy Windows desktop applications. Why do you need it? If you try to run the installer and
