I am running a windows 2003 Domain. I have some computers on my network (all running windows 2000) which will lock 10 minutes after a user has logged off.
It displays a message that says
"The Computer is in use and has been locked.
or and administrator can unlock this computer.
Press Ctrl-Alt-Del to unlock this computer"
When i press Ctrl-Alt_del it displays a blank username and password.
I've also looked in the evet veiwer and have only found one event that could be related to this is
"Application popup: Unlock Computer: winlogon.exe - Application Error : The instruction at "0x7c596e81" referenced memory at "0x00020048". The memory could not be "read".
Click on OK to terminate the program
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp