Can't logoff or shutdown? oops

[Mark whalen]

Hello all,
i am using windows XP with service pack 1. I can't
logoff or shut down my computer from the startbar. yes
they are enable and the confimation dialog boxes do apear.
There is an exception to the rule, i can switch user to
get back to the log on screen, once back at the logon
screen i can click shutdown to shutdownt the computer
withour errors. btw I don't get any errors when windows
fails to shut down. On a possible related note, explorer
will somtimes crash and restart with tthe error message
internet explorer has had an error, ok only box,
following error says failed to create window,( i can't
follow links, or create a new window.

Thanks in advance,
Mark whalen