People who work in a support environment may know the following
scenario: User calls he works on an XP based terminal or production
control Pc ,which he/she shares with users from the morning,day and night
shift.He/she has forgotten his/her password and requests a reset.OK.Done.
Later that day the user from the next shift calls,who logs in with the
same account and claims he/she cannot login.Wrong password.If you have
luck your phone is ringing with that user,and you can tell that the password
has been reseted due a request from the shift before.If not another agent
picks the call,resets the password again and it is just a question of time
untill the night shift calls with a password problem.
These are reminiscent memories from my early days in IT : ))

To prevent this situation,make sure the users on the affected Pc use the
same user account and navigate to : (accessing the affected Pc through
network registry !!)

- HKEY_CURRENT_USER\Software\Microsoft\Windows
Windows\CurrentVersion\Policies\Explorer\

Add in the Explorer subkey in the right pane the entry:
NoLogOff (right click , new , REG_DWORD [DWord Value] )
and set its value to 1.
This will remove the Log Off function from the Start Menu.Setting the
value to 0 will show it again.