So I am almost literally going insane due to this error, from what I could see it's pretty common, the thing is no solution works for me, I have tried going to Microsoft for help using their website, http://support2.microsoft.com/kb/976982/en , but none of the 3 solutions presented work, none, I've tried re-installing .NET Framework both by uninstalling it at the Control Panel, and by using the clean up tool but the problem is that when I try to install it again I get error 643, same error I get when I try to update, either through windows update or by downloading the update myself. I also can't complete the 3rd solution suggested by Microsoft, the first step of that solution is uninstalling .NET Framework using the clean up tool, and then installing .NET Framework 1.1, then installing .NET Framework Service Pack 1, and then .NET Framework 3.5 Service Pack 1. The thing is I can install .NET Framework 1.1, but if I try to install .NET Framework service Pack 1 it gives me an error saying it can't access windows installer or something like that, and .NET Framework 3.5 SP1 guess what hows up, error 643 :DDDD!!!!!
So yeah after that I just restored .NET Framework and came here to ask for a solution, so I can finally put this error to bed and update windows. Cheers
PLEASE NOTE that I have tried the other solutions suggested by Microsoft including using fix it, repairing .NET Framework by going to the control panel and doing that uninstall/modify option and using the repair tool
Windows Update Code 643
It's linked to 3 Windows updates (KB3008627, KB3000988 & KB2918614). After the 3 uninstall reboot. After uninstalling these updates, we temporary hid the updates to prevent the reinstallation of them, then installed .NET 4.5.2 using Windows Updates and rebooted. Don't forget to update also your Pack language of .Net 4.52. Once installed, we un-hid the uninstalled updates and reinstalled them.