How can I set a users time zone information for them?

Q: I ran the MSEXTMZCFG.exe file yesterday and ended up with about 25% of my users in the NonExistent.txt file - how can I set their time zone for them - is that setting in the Registry?
A: Do you know the time zone of the 25%? If it's the same time zone, you can take that nonexistent.txt file and assign the single time zone and run the tool against them. E.g. (tab mailservername tab) see the mailboxes_1.txt file -- you can copy and paste the end of the line for these users. If they are in multiple time zones, you should diagnose further. (E.g. - how many mailxobes are impacted? How many time zones do they cross, etc.?)