Hello Andrew,

The projects won't get lost. It seems only that the .NET Installation is corrupt and asks you to register it but it will not delete the projects already  made.

Please try to uninstall the .NET Framework 3.5 and then use this cleanup tool:

http://cid-27e6a35d1a492af7.skydrive.live.com/self.aspx/Blog_Tools/dotnetfx_cleanup_tool.zip

Once done reinstall the .NET Framework 3.5 from following link:

http://www.microsoft.com/en-us/download/details.aspx?id=21

Please keep me updated.

If I may ask .. how can I find the .NET Framework for uninstall it?

Thanks ..

Look under:

C:\Windows\Microsoft.Net\Framework\V...

Hello Andrew,

You can also use the cleanup tool to uninstall the .NEt Framework 3.5. This tool will perform a silent uninstall and cleans the system from the files of the framework.

Many thanks!

Thanks, just another question. If I use the cleanup tool will it cause me to lose any other files stored on my harddrive?

The part I put a rectangle around is what made me think it might delete software and files on my laptop.

Hello Andrew,

It will not delete software form your computer but since it deletes the framework in silent mode and some frameworks are connected, this message has been added. The .NET 3.5 is a standalone Version and since you will reinstall it after, nothing will happen.

Many thanks!

The .NET Framework uninstalled for me however it will not reinstall. I have tried several times and it keeps coming up as a 'Setup Error'. Please find a download for me that will actually work as I have 3 websites in my software that have had to be updated several times since 2 months ago and I cannot update them because of this problem. I am very annoyed ... 

Hello Andrew,

Can you please tell me what Windows Version do you have on your computer?

If you have Windows 7 you can follow the visual tutorial on following website:

http://csharpdotnetfreak.blogspot.com/2012/06/install-net-framework35-sp1-windows7.html

Many thanks!