Do you have the KB2901983 NET Framework 4.5.2 Update Problem too?
Then you know this message: .NET Framework 4.5.2 für Windows 7 (KB2901983) could not be installed (Fehlercode: 643)
The reason is, according to Microsoft a corrupted MSI software update registration.
Try the following steps:
- Download this Microsoft Fix (direct download expired, follow the link and go til step 3, so you can download the patch)
- close all programs
- KB2901983 should now be installed easily
Good luck! ;-)