It is a 'Profiles' issue.
You must 'establish' the parameters for each and every individual user profile.
And, even then it may not work.
There are some so-called 'work arounds' but they are not so smple to describe and it would be best for you to 'exhaust' other efforts first.

Or, blow out Vista and install XP without Service Pack 3 !

Isn't Vista more fun than a hat-full-of-***holes ?

__________________
Fusion for REAL!--CDex 1.51--Wackyuses--Bitzi - Check Files Before Download !--.mp3 File Name Change Problems? Try Rename-It!--Alternate PORTS--Avast- Anti-Virus--WindowWasher--IrfanView--PC Pitstop - Test your PC !--Mac OSX Troubleshooting--GO .ape ! - For 'Lossless' Audio Compression--Port :6346 - Test If It Is 'Blocked'--Cole2k Codecs--OldVersion - Newer isn't always better !
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Tomorrow's forecast:
Sunni in places, Shi'ite in others...