Cannot reinstall .net framework 2.0 service pack 1
I just installed QuickBooks Pro 2008 & it was running well. Today QuickBooks not start and after diagnosing the problems it appears to be related to a corrupt .net framework 2.0 service pack 1. I tried to uninstall it and got the error "the source cannot be found". I then used the Windows Cleanup utility to uninstall it. After a reboot I tried to reinstall it and got the error it is already installed (even though it does not show up in Add/Remove Programs.
How can I make sure all traces of .net framework 2.0 service pack 1 are removed from the registry or is there another utility I can us to make sure it is completely remove it. QuickBooks will not run without it. My system is Windows XP Professional SP2 with IE 7.0 & all current Windows updates.