After playing with some Group Policy settings and breaking privileges for System accounts, I have learnt the hard lesson to have a proper configuration management policy in place. So that will cover the future, but the current messup, can I either;
Restore the Group Policy files ontop of the SYSVOL folder from a recent tape backup?
Piece together the old policy - I have looked at a previous backup and found the GptTmpl.ini file under MACHINE\Microsoft\Windows NT\SecEdit, with what appears to be all the settings to be applied, however, most of the Users/Groups have been converted to their SID equivelants which I don't know what users/groups they equate to. I found the whoami tool, but I couldn't see an option to specify a user to show details!
Tips / warnings would be greatly appreciated,