Error Message when logging on "The Group Policy Client service failed the logon. Access is denied"

Question

Since the move to Windows 7 we have started getting this error above when people login at random times and on random machines, at first we thought it was only a select few users, but now it seems to have occurred to about 20 different Staff members working
at the school. Also of those 20 odd users it has happened to them on a few occasions.
What we know
We know this problem is only occurring to staff with Roaming Profiles, it seems like somehow the profile is not Synchronizing with the Servers File Share that houses the profiles, which causes the NTUSER.DAT file to become corrupt and go from being around
2 – 3 MBs to 256KB (In all cases where a user has had this issue there NTUSER.DAT file has been 256KB)
Current Resolution to the problem
When a staff member contact us with this problem, we fortunately have Previous Versions working on the profiles folder on the server, so we are able to restore their NTUSER.DAT file from 1 to 2 days before it became corrupt, which then seems to allow them
to log on fine
What we have tried so far & suggested so far
After some research on Google, we found the following thread on EduGeek
http://www.edugeek.net/forums/windows-7/78733-windows-7-user-profile-failed-error-again.html#post700415
Which suggested that the problem may lay within registry, so we implemented the Script that was posted on the website, however this has not seemed to make any difference
In the early stages when only 5 – 10 staff seemed to be having the problem, we believed the issue could be with just certain AD accounts. It had not seemed to happen to any recently created AD accounts so we thought it could be a corrupt attribute on
the user so we delete one of the staff AD accounts that had the problem and creating a brand new one, however within about 2 – 3 weeks that staff member had the issue occur again
Leading on from point two, we also thought the problem could be with people using multiple computers, logging on in 2 places and not logging off properly, but unfortunately the staff member referred to in point 2 only uses the one computer in reception.
Another potential cause that we figured might be the route of the problem, was it could be specific computers that are not communicating properly with the server, which could be causing this problem to occur, but we have no real way of testing this,
as the staff generally log onto 3 – 4 different computers throughout the day and in different location
We log a call with EE and they just pointed us to various websites that we had already checked and wasn’t much help.
In Summary
This error has now occurred with about 20 members of staff, we currently only use Windows 7 at our Senior School & Moving to Windows 7 at our Prep School in the Summer
holidays, we would like to find out the route of this problem ideally before then, as we could potentially be doubling the amount of staff with the problem after the move. Has anyone else seen this problem or have a brain wave on how to solve it?
Regards
Andy

Answer 1

Hi Dudleya,
First of all ,I would suggest to check the permissions of the NTUSER.DAT registry hive .Here is a link for reference :
The Group Policy Client service failed the logon. Access is denied(Juke Chou`s answer)
https://social.technet.microsoft.com/Forums/windows/en-US/8c0054a3-35be-4fc4-839c-e2176613eb23/the-group-policy-client-service-failed-the-logon-access-is-denied?forum=w7itpronetworking
Please refer to this link and add the registry keys to have a check .Please backup the registry keys before you made modifications to them.
The Group Policy Client Service Failed The Logon In Windows 8(It should also work on windows 7 )
http://www.thewindowsclub.com/fix-group-policy-client-service-failed-logon-windows-8
If the issue persists ,we can refer to this link to troubleshoot this issue .
Troubleshoot User Profiles with Events(It should also be applied to windows 7 )
https://technet.microsoft.com/en-us/library/jj649075.aspx
NOTE: This response contains a reference to a third party World Wide Web site. Microsoft is providing this information as a convenience to you. Microsoft does not control these sites and has not tested any software or information found on these sites.
Best regards