I have a Windows 2000 server which was running fine until a UPS
problem this morning caused it to cut out. When it finished booting
back up 5-10 minutes later, ALL of my Windows NT workstations started
giving the error "The system could not log you on to this domain
because the system's computer account in its primary domain is missing
or the password on that account is incorrect" when anyone tries to log
on. The WinXP stations are fine.

Sounds like an encryption problem , try sending password unencrypted

Hi corwin02-ga,  Thanks for the reply.  But it is not a password
problem because if I give wrong password then it gives proper message
like "Invalid password"

Have you tried removing one of the NT Workstations from the domain and
then adding it back in?

Otherwise it could be a naming issue are the work stations on the same
subnet as the 2000 server?  You may need to check your LMHOST files or
wins server. Can you logon to a workstation locally and ping the
server by name from there?

The password it is talking about is the computer account password,
which is not something that you can just type in etc.

Try removing one of the NT4 Workstations from the domain and rejoining
it. Make sure that you delete it's computer account after you remove
it from the domain. This should force it to create a new computer
account and should allow it to login. If that fixes it and if you
don't have a lot of systems I'd jus go to each one and follow the same
procedure.