When you try to restore Windows Vista to an earlier date, you get the following error message: “vss error, volume shadow copy service error instantiating vss server. Error 0×80070422″.

This message, although it looks like it’s a Windows Update error (judging by the error code), is caused by the absence of the Volume Shadow Copy service.

To fix this problem, you need to start this service. Go to the Control Panel, open Administrative Tools, then Services and select Volume Shadow Copy from the list. Double click to open it and click on the Start button. This will enable the service. Also, under Startup type, select Automatic from the drop down list. Click OK and close all windows.

Restart the PC and try to restore the system. It should work now.