Problem wit a Domain Admin account with .exe files

RUn Regedit > Windows cannot access the specified device, path …..etc
Or when I tried to start Server Manager

if i look at file permissions it says administrators and system have full control
my domain account is ia Domain Admin
but i still get access denied, if i add my name to the regedit.exe directly along side administrators it works.
any reason why the group doesnt seem to be working?

windows 2008 R2