Man, I just spent hours today googling around to find the answer to failing updates of Service Pack 1 to .NET Framework 2.0. The error, 0x643, told me to try the update again, which was useless.
This server was running Data Protection Manager 2007, so it had SQL Server 2005 installed also, which was crashing on startup. This seemed to indicate a corrupted install of .NET Framework 2.0.
Well, luckily, or so I though, that is what the built in "Repair" option is for under change/remove in Add/Remove Programs. Unfortunately, it failed, saying that there were invalid characters in the path "Program Files". This was a hint, but not a very good one. I spent hours trying to find other ways to "repair" the problem, since I couldn't really uninstall the Framework.
Finally, I stumbled across a single blog post from a user named "favorini" which had the magic hint, especially given the message I received when I first tried to repair it.
Aaron Stebner's WebLog
The answer to this problem was to run regedit, find all of the references to D:\Program Files, especially the ones with "D:\Program Files\Common Files\Microsoft Shared\DW", which is a leftover from a bug where Dr. Watson was installed on the D: drive instead of the C: drive, even though D: was a CD drive. Find all of those and change them to reference "C:" instead of "D:".
Just ick.
As always, be careful editing the registry, etc. etc. yada yada.
I hope this helps someone out there.
