I wonder why Adobe needs UAC turned on though,.. I've installed other apps w/o issue.
If you go to System properties, and look at the environment variables, there's two set of "TEMP" variables... one user level, and the other system level. Most applications use the system level TEMP variable to find a temporary directory to extract to. e.g. "\windows\temp". But Adobe for some reason is using the user-level TEMP directory (\users\me\appdata\blah-bla-blah", which has tighter security in Vista, than under XP. System-level \windows\temp doesn't have as many restrictions.