Event ID 1081 Userenv

Windows cannot impersonate the user. (The handle is invalid. ). Group Policy
processing aborted.
User: NT AUTHORITY\SYSTEM
Source: Uerenv
Error occurs every 100 to 110 minutes.

With fast user switching turned on, if I log out or lock the computer with
Window+L, I cannot log into any account, the only way I can get back in is to
restart the computer.
The only possible explanation I have is that either WinPooch is trying to do
something without permission or another networked Win2000Pro computer is
asking forpermissions it does't have. Neither of these seem likely as it is
not related to network traffic. after a full system scan by AVG, Kasperky,
Norton, AdAware, Windows Defender, a-squared and Spybot, the system comes up
clean.
The first Userenv error (Event ID 1517) began on 4Jun06 as a warning, then
the error (Event ID 1081) began 10Aug06.
I am shutting down WinPooch for now to see if that is the cause but would
appreciate assistance with other possiblities.

I'm getting this error also. It only seems to happen when I'm at the
welcome screen and logged in. Sometimes windows "locks" me out by
refusing my password and the only remedy is to reboot. Is there a
definitive cause/fix for this error?


--
graysky