Administrator unable to unlock a "locked" computer

Applies To
Windows

Symptoms

After you restart a computer running Windows and no one has signed in, you may be unable to sign in to the computer either locally or to the domain.

The following error message may be displayed at sign in:

Note

This computer is in use and has been locked.
Only or an administrator can unlock this computer.
Press Ctrl + Alt + Del to unlock this computer.

If you try to unlock the computer, the following error message may be displayed:

Note

This computer is locked. Only or an administrator can unlock this computer.

If a user has signed in and signed out, you may be unable to sign in to the computer (locally or to the domain) and the following error message may be displayed:

Note

This computer is in use and has been locked.
Only domain\username or an administrator can unlock this computer.
Press Ctrl + Alt + Del to unlock this computer.

If you try to unlock the computer, the following error message may be displayed:

Note

This computer is locked. Only domain\username or an administrator can unlock this computer.

NOTES

  • In the error messages above, domain is the domain name of the last user who signed in to the server and username is the name of the user who last signed in to the server.

Cause

This behavior can occur for either of the following reasons:

  • When the default screen saver is set to use a nonexistent screen saver program.
  • When you use a corrupted screen saver that's password protected.

Resolution

Important

This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, select the following article number to view the article in the Microsoft Knowledge Base:

322756 How to back up and restore the registry in Windows

To resolve this problem, use another screen saver program (such as Logon.scr) that's installed locally on the system or that's not corrupted.

  1. Start Registry Editor (Regedt32.exe).

  2. Locate the Scrnsave.exe value under the following registry key:
    HKEY_USERS\.Default\Control Panel\Desktop

  3. On the Edit menu, select String, type logon.scr, and then select OK.

  4. Locate the ScreenSaverIsSecure value.

  5. On the Edit menu, select String, type 0, and then select OK.

  6. Quit Registry Editor.

WORKAROUND

To work around this problem, use the appropriate method.

Method 1: When the Error Message States the Computer Is Locked by domain\username

  1. Press CTRL+ALT+DELETE to unlock the computer.
  2. Type the sign-in information for the last signed-in user, and then select OK.
  3. When the Unlock Computer dialog box disappears, press CTRL+ALT+DELETE and sign in normally.

Method 2: When the Error Message Does Not State Who Locked the Computer

  1. Use the Shutdown tool in the Microsoft Windows Resource Kit and attempt to shut down the locked computer. The System Shutdown dialog box is displayed on the locked computer, but the computer doesn't restart.

  2. When the shutdown timer expires, the Welcome to Windows dialog box is displayed.

  3. Before the screen saver becomes active, press CTRL+ALT+DELETE, and sign in normally.

Note

If you don't use one of these methods to sign in, you must restart the computer and sign in before the screen saver program starts.

Status

This behavior is by design.