http://support.microsoft.com/default.aspx?scid=kb;EN-US;279664 is a resouce kit that allows you to remotely set local logon rights for a remote machine....
Download the tool and then:
ntrights -m \\ProblemComputer -u Administrator +r SeInteractiveLogonRight
Thi
s should give them the local logon rights
-r SeDenyInteractiveLogonRigh
t may have to be used if the Administrator is a member of a group that got set to Deny.
ntrights -m \\ProblemComputer -u ProblemGroupName -r SeDenyInteractiveLogonRigh
t