When you try to open Windows Task Manger, the following error may appear: "Task Manager has been disabled by your administrator"

Cause :

  1. You use account that was blocked via the "Local Group Policy" or "Domain Group Policy".
  2. Some registry settings block you from using "Task Manager"

Resolution:

To resolve the issue, follow the steps below:

  1. Verity that the "Local Group Policy" doesn’t block you from using Task Manager.
    1. Go to "Start" -> "Run" -> Write "Gpedit.msc" and press on "Enter" button.
    2. Navigate to "User Configuration" -> "Administrative Templates" -> "System" -> "Ctrl+Alt+Del Options"
    3. In the right side of the screen verity that "Remove Task Manager"" option set to "Disable" or "Not Configured".
    4. Close "Gpedit.msc" MMC.
    5. Go to "Start" -> "Run" -> Write "gpupdate /force" and press on "Enter" button.

    Note: If you are using Windows 2000, please follow the below Microsoft article instead stage "e".

    http://support.microsoft.com/kb/q227302/

  2. Verify correct registry settings:
    1. Go to "Start" -> "Run" -> Write "regedit" and press on "Enter" button.
    2. Navigate to the following registry keys and verity that following settings set to default:
      Windows Registry Editor Version 5.00

      [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\
      System "DisableTaskMgr"=dword:00000000

      [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Group Policy Objects\LocalUser\Software\Microsoft\Windows\CurrentVersion\
      Policies\System] "DisableTaskMgr"=dword:00000000

      [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
      policies\system\]"DisableTaskMgr"=dword:00000000

      [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon] "DisableCAD"=dword:00000000

    3. Reboot the computer.

TKB:1051