Svr2k prob after changing admin passwd

Exactly what event id is being returned? And which log is it in?

Event Type: Error
Event Source: Userenv
Event Category: None
Event ID: 1000
Date: 26/07/2005
Time: 02:54:48
User: NT AUTHORITY\SYSTEM
Computer: 2KSVR
Description:
Windows cannot determine the user or computer name. Return value (1326).

It's in the Application log

you worry that temporarily unjoining your domain controller might upset things huh. me too...
yeah, that article looked good until you realize you are on a domain controller.
i have never heard of this one and sounds like bfilm maybe hasn't either.
i don't see how your password changed would have anything to do with an Active Directory dns registration error. i think maybe you had this error before but just noticing now after checking things over.
i would go to mskb and find the article about how to check out your dns to see if it looks set up right. if i get a chance i will find the link for you...
me thinks you are leaving a whole lot of what has been happening unmentioned...
if in your shoes, i would pop out my cc and call microsoft. you may get free support. you can get it fixed and be all ears to learn something to help justify the expense. it'll be worth it and your cust will see you doing what ever it takes to get it fixed (way to go...)

The return value on your Event ID "1326"
does not pertain to the link you posted
search eventID.net (If you're not a member - join, it's worth it). It appears as though the "1326" return code is from some service, script, scheduled task etc. that you overlooked
changing the user of what context it runs under.