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How to Install .NET Framework 3.5 on Windows 8.

If you have tried to install an application on Windows 8 computer that requires an older version of .NET framework you might receive the following error:

Windows couldn't complete the requested changes.

Windows couldn't connect to the Internet to download necessary files. Make sure that you're connected to the Internet, and click "Retry" to try again.

If the video tutorial didnt work the follow this steps:
go to control panel, change view type to small icons on the top right, click windows update, click on # important updates are available link and there select .NET frame work if is not already pre selected click on install button