Screensaver password works even if account is locked out

If account lockout option and password protected screen saver are enabled and the user tries to get past the screen saver password unsuccessfully, it increments the account lockout counter. Numerous bad attempts should result in the domain account being locked out. The problem is that the screen saver password does not check to see if the account is locked out. So, if the account lockout counter is set to five bad attempts before locking the account, the screen saver lets the user in if a correct password is entered even after five bad attempts.

This is the expected behavior. To change this default behavior so that the screen saver keeps track of bad password count and locks the account once the bad password count is reached, please apply service pack 4 and the registry entry mentioned in the Resolution section.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To install the fix:

1. Click Start, Run, type REGEDT32 and click OK.
2. Navigate to the key HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon.
3. If the ForceUnlockLogon value does not exist, add it. To do so click Edit, select Add Value, type ForceUnlockLogon, change Data Type to REG_DWORD and click OK. When the DWORD Editor opens, add the number 1 into the Data field and ensure Hex is selected, then click OK. The ForceUnlockLogon should appear in the right pane of the Winlogon screen.
4. Close the Registry Editor.
5. Restart the computer.
   

Microsoft has confirmed that this is a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.