Appatic

You can use the  .NET Framework Cleanup Tool In the case you have encountered a issue where you cannot uninstall a .NET Framework Component, It gives you a .NET related error when you want to install .NET apps, you find yourself unable to solve a problem with your .NET Framework Components.

It is not a common uninstaller or fixer, so it should only be used in the case of conflicts and errors. But if you have them it will remove .NET completely unless you are in a OS version that got a .NET component that is restricted for uninstalling by design. But don’t worry it is very likely that such component is not the one giving trouble. Even then it should return it to a stable state if that would be the case.

Once you use the app, you should be good to install back again, if you find it too much of a hassle to install it completely manually. you can use something like the All In One Runtimes Installer so it does it for you. Once completed everything should be fine.

This is of course the short version of what and how this app works, so if you want to know in more detail you should check out Developer Aaron Sterbner post on it.

.NET errors are rare and when they happen, it is usually because of a bad installation of a .NET app or because something is wrong in the OS configuration. But if you have a issue, they are quite hard to resolve, so this app should come quite handy. It works for XP and Vista.

Linkage

.NET Framework Cleanup Tool User Guide     <—A Must Read

.NET Framework Cleanup Tool                             <—Download Page

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