unable to logoff/shutdown via RDP

[cdurre]

I am running into an issue where I cannot logoff/shutdown a machine
while logged in via remote desktop. The machine is running XP pro SP2.
I am able to log out and shutdown the machine while logged in locally
on the console. However, when logged in via remote desktop, I get the
following error when trying to shutdown:
Date: 10/10/2005 Source: USER32
Time: 11:34:08 AM Category: None
Type: Warning Event ID: 1073
User: NT AUTHORITY\SYSTEM
Computer: COMPUTERNAME

Description:
The attempt to reboot COMPUTERNAME failed

For more information, see Help and Support Center at
http://go.microsoft.com/fwlink/events.asp.

All microsoft has to say is this:
Details
Product: Windows Operating System
ID: 1073
Source: USER32
Version: 5.2
Symbolic Name: WARNING_EW_SHUTDOWN_CANCELLED
Message: The attempt by user %2 to restart/shutdown computer %1 failed

Explanation
This event is written when a user or application attempts, but fails,
to restart or shut down the computer by using either the graphical user
interface (GUI) or the shutdown command.


User Action
If you still want to restart or shut down the computer, save any open
files, close any applications that are running, and then you can:

Use either the graphical user interface (GUI) or the shutdown command
again.
Press CTRL+ALT+DELETE, and then while pressing CTRL, click Shut Down to
force a shutdown.
Press the reset or power button on the computer.



I am able to force a shutdown remotely from the command line: shutdown
-f -r

However, a shutdown -r doesn't work. Additionally, I don't know of a
way to force a logoff without rebooting. The fact that I can shutdown
and logoff normally from the console but not while logged in remotely,
makes me think that there might be an RDP bug somewhere, but I haven't
found anything online. I have shutdown all unnecessary services and
still gotten the same results. The following is a list of processes
currently running.
ATI2EVXX.EXE(SYSTEM), CRSS.EXE(SYSTEM), CRSS.EXE(SYSTEM),
Explorer.EXE(user), LSASS.EXE(SYSTEM), rdpclip.exe(user),
SERVICES.EXE(SYSTEM), SMSS.EXE(SYSTEM), SPOOLSV.EXE(SYSTEM),
SVCHOST.EXE(SYSTEM), SVCHOST.EXE(NETWORK SERVICE), SVCHOST.EXE(SYSTEM),
SVCHOST.EXE(NETWORK SERVICE), SVCHOST.EXE(LOCAL SERVICE),
SVCHOST.EXE(SYSTEM), System(SYSTEM), System Idle Process(SYSTEM),
taskmgr.exe(user), UPHCLEAN.EXE(SYSTEM), WINLOGON.EXE(SYSTEM),
WINLOGON.EXE(SYSTEM)

Any ideas here would help.

Cedric