What if win8.1 can't connect to a Windows service?
Solving method
1. Enter the Win8.1 security mode and record the user name that the user's computer needs to log on (that is, a problem, a username that cannot be logged in) (for example, Administrator);
2. After entering the safe mode, find C:\windows\regedit.exe, double-click the regedit file, and open the Registry Editor;
(or click on the Start menu, then enter regedit in the "Start Search" and click "Regedit.exe")
3. In the Registry Editor, find "HKEY_CURRENT_USER", right click on this item;
In the same way, add the user "system" and set Full Control permissions.
4, restart the computer, and select their own account login can.
These are the full contents of the Win8.1 hint that you cannot connect to the Group Policy Client service, and you can log back in to the account by adding the user's highest privileges.