Windows update Error Code: 8000FFFF

Solution

1. Open Regedit.exe

2. Navigate to HKEY_LOCAL_MACHINE\COMPONENTS

3. Delete the Entries, PendingXmldentifier, NextQueueEntryIndex, AdvancedInstallersNeedResolving

4. Download the Windows update agent and reinstall it.

For x86: http://download.windowsupdate.com/WindowsUpdate/redist/standalone/7.0.6000.381/WindowsUpdateAgent30-x86.exe

For x64: http://download.windowsupdate.com/WindowsUpdate/redist/standalone/7.0.6000.381/WindowsUpdateAgent30-x64.exe

5. Stop the BITS and Windows update service.

6. Rename the Software Distribution folder and %windir%

7. Start the BITS and windows update service.

8. Reboot the machine

9. Try to Windows update again.