auto login to windows 2000 terminal server (admin mode)

hi,

I have some problem with me ISA 2004 server on windows 2000 server
computer.

Since last week someone stole my Admin Password and made that every one
that connent to my ISA server via remote desktop can login automaticly
as administrator.... (full access to everything...)

I can't find where he put the password or the username.

It happans only from remote desktop and not happans when you are
locally.

I changed my admin password and now it's try to login and gives an
error about user name or password.


any Idaes????

thanks....