Login loop for XP SP2 users

[Computerguy]

We have a problem where users are logging into the network then
promptly being returned to the login screen. Does anyone know how to
resolve this ? We are running Windows XP SP2. This happens with more
than one user. Thanks.

 

[Guest]

We have a problem where users are logging into the network then
promptly being returned to the login screen. Does anyone know how to
resolve this ? We are running Windows XP SP2. This happens with more
than one user. Thanks.

I have a XP Home SP1 exhibiting the same problem.
Did a system repair... no effect.
Switched to VGA mode (thought it was a video problem) Got a little farther,
NOGO.
Problem continues on the Administrator account.
Cannot get to the command prompt. Would consider a full reinstall, but do
not want to lose the data.

Tks