Does anyone know why Dial-a-fix sometimes gets an "unspecified error" while trying to unregister MSXML3.DLL? It seems to be new because it's never done that in the past. Apparently you can immediately try it again and Dial-a-fix will then be able to unregister/re-register it. It's weird.

(Update: see the comments for a possible explanation. Short version: just run the same parts of Dial-a-fix again and you shouldn't get the error. If you still have trouble with Windows Updates, try clicking "Flush SoftwareDistribution".)