After trying everything described here (except a clean install, because I wanted to keep my applications) I looked into a crash dump file (in C:$WINDOWS.~BT\Sources\Rollback) using windbg.exe (no idea why I haven't done that earlier ...). This told me what the probable crash candidate was: The ueye GigE camera driver. AND: This was correct. After uninstallling the ueye software including the drivers the update went through.
Maybe that helps at least some of you ...
This is very interesting -- thank you for sharing. I found several files/drivers it mentions -- how were you able to tell which one was faulty? I see several pieces of software it mentions which could be problematic.