After many hours on Google this is what I found and it worked.
http://forums.cnet.com/5208-6142_102-0.html?forumID=44&threadID=249476&messageID=2496438 (http://forums.cnet.com/5208-6142_102-0.html?forumID=44&threadID=24...6&m)
by Grif Thomas - 5/25/07 7:21 PM
In reply to: Media Center has stopped working by bifera
Visited the computer manufacturer's website and checked for updated video and audio drivers? If not, please do.. If nothing new is at the computer manufacturer's site, please check the video and audio card provider's site.. New drivers are coming out frequently for Vista and it's always worth a check.
Another thought also... Because of the "Problem Signature 09: System.UnauthorizedAccess" listing, please find the Media Center icon in your start menu, RIGHT click on it, select "run as Administrator". See if that helps.
Hope this helps.
Grif
Also
Thanks for that - I found the problem with MS technical support yesterday.
The issue was over permissions for the user. The account was computer
administrator (as created in in MCE), but somehow the permissions for the
user were screwed - probably in the upgrade to Vista HP. The problem became
evident when we tried to rename the ehshell.exe as part of the diagnostic
process - I did not have permissions to do this which was strange - refused
to let me grant full control over files in the folder. The solution was to
create a new user. MC worked straight away when I logged in with the new
account.
Thanks for the posts - hope this helps someone else.
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