That's what I thought, but I have one server that
says "you have exceeded your maximum number of
connections" when more than one admin logins. Do I have
to tell it somewhere to have more than one connection?
No, 2 concurrent connections is the default.
There's probably a disconnected session still hanging around. You can
check (and reset) that in TS Manager.
If you configure a time-out limit on disconnected sessions, you can
reset them automatically and avoid being locked out.