Windows 7 Error: "Failed to connect to a windows service" when logging in

Error:
Failed to connect to a windows service
Windows could not connect to the Group Policy Client service. This problem prevents standard users from logging on to the system.

Users may also see:
Event ID 6003

The winlogon notification subscriber was unavailable to handle a critical notification event.
Environment:

Windows 7 Professional


Resolution:

 

1. Create a reg file on your desktop with the settings contained farther down
2. Run regedit.exe as an administrator.
3. Locate HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\gpsvc and export it to your desktop. This is used as a backup just in case something goes wrong.
4. Right click on gpsvc select Permissions.
5. Click Advanced.
6. Click the Owner tab.
7. Under Change Owner to, highlight your current user and then click ok
8. Close out of permissions.
9. Right click on gpsvc select Permissions.
10. Click Administrators, check full control.
11. Click OK and close the permissions window.
12. Right click on gpsvc, delete it.
13. Run the regfile created in step 1.
14. Reboot.

Reg File:

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\gpsvc]
"PreshutdownTimeout"=dword:000dbba0
"DisplayName"="@gpapi.dll,-112"
"Group"="ProfSvc_Group"
"ImagePath"=hex(2):25,00,73,00,79,00,73,00,74,00,65,00,6d,00,72,00,6f,00,6f,00,\
  74,00,25,00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,73,\
  00,76,00,63,00,68,00,6f,00,73,00,74,00,2e,00,65,00,78,00,65,00,20,00,2d,00,\
  6b,00,20,00,6e,00,65,00,74,00,73,00,76,00,63,00,73,00,00,00
"Description"="@gpapi.dll,-113"
"ObjectName"="LocalSystem"
"ErrorControl"=dword:00000001
"Start"=dword:00000002
"Type"=dword:00000020
"DependOnService"=hex(7):52,00,50,00,43,00,53,00,53,00,00,00,4d,00,75,00,70,00,\
  00,00,00,00
"RequiredPrivileges"=hex(7):53,00,65,00,49,00,6d,00,70,00,65,00,72,00,73,00,6f,\
  00,6e,00,61,00,74,00,65,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,\
  65,00,00,00,53,00,65,00,54,00,63,00,62,00,50,00,72,00,69,00,76,00,69,00,6c,\
  00,65,00,67,00,65,00,00,00,53,00,65,00,54,00,61,00,6b,00,65,00,4f,00,77,00,\
  6e,00,65,00,72,00,73,00,68,00,69,00,70,00,50,00,72,00,69,00,76,00,69,00,6c,\
  00,65,00,67,00,65,00,00,00,53,00,65,00,49,00,6e,00,63,00,72,00,65,00,61,00,\
  73,00,65,00,51,00,75,00,6f,00,74,00,61,00,50,00,72,00,69,00,76,00,69,00,6c,\
  00,65,00,67,00,65,00,00,00,53,00,65,00,41,00,73,00,73,00,69,00,67,00,6e,00,\
  50,00,72,00,69,00,6d,00,61,00,72,00,79,00,54,00,6f,00,6b,00,65,00,6e,00,50,\
  00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,53,00,\
  65,00,63,00,75,00,72,00,69,00,74,00,79,00,50,00,72,00,69,00,76,00,69,00,6c,\
  00,65,00,67,00,65,00,00,00,53,00,65,00,43,00,68,00,61,00,6e,00,67,00,65,00,\
  4e,00,6f,00,74,00,69,00,66,00,79,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,\
  00,67,00,65,00,00,00,53,00,65,00,43,00,72,00,65,00,61,00,74,00,65,00,50,00,\
  65,00,72,00,6d,00,61,00,6e,00,65,00,6e,00,74,00,50,00,72,00,69,00,76,00,69,\
  00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,53,00,68,00,75,00,74,00,64,00,\
  6f,00,77,00,6e,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,\
  00,53,00,65,00,4c,00,6f,00,61,00,64,00,44,00,72,00,69,00,76,00,65,00,72,00,\
  50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,52,\
  00,65,00,73,00,74,00,6f,00,72,00,65,00,50,00,72,00,69,00,76,00,69,00,6c,00,\
  65,00,67,00,65,00,00,00,53,00,65,00,42,00,61,00,63,00,6b,00,75,00,70,00,50,\
  00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,00,00
"FailureActions"=hex:80,51,01,00,00,00,00,00,00,00,00,00,03,00,00,00,14,00,00,\
  00,01,00,00,00,c0,d4,01,00,01,00,00,00,e0,93,04,00,00,00,00,00,00,00,00,00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\gpsvc\Parameters]
"ServiceDll"=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,\
  00,74,00,25,00,5c,00,53,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,\
  67,00,70,00,73,00,76,00,63,00,2e,00,64,00,6c,00,6c,00,00,00
"ServiceMain"="GroupPolicyClientServiceMain"
"ServiceDllUnloadOnStop"=dword:00000001
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\gpsvc\Security]
"Security"=hex:01,00,14,80,8c,00,00,00,98,00,00,00,14,00,00,00,30,00,00,00,02,\
  00,1c,00,01,00,00,00,02,c0,14,00,02,00,0d,00,01,01,00,00,00,00,00,01,00,00,\
  00,00,02,00,5c,00,04,00,00,00,00,00,14,00,ff,01,0f,00,01,01,00,00,00,00,00,\
  05,12,00,00,00,00,00,18,00,8d,01,02,00,01,02,00,00,00,00,00,05,20,00,00,00,\
  20,02,00,00,00,00,14,00,8d,01,02,00,01,01,00,00,00,00,00,05,04,00,00,00,00,\
  00,14,00,8d,01,02,00,01,01,00,00,00,00,00,05,06,00,00,00,01,01,00,00,00,00,\
  00,05,12,00,00,00,01,01,00,00,00,00,00,05,12,00,00,00

Credit
Parts of this post came from a user called NarenXP. I expanded and added additional steps needed to complete the fix on Windows 7.