Windows XP Pro User Permissions

I'm currently using Windows XP Professional Edition. For some reason all my accounts including the administrative accounts are limited to guest priviledges. All my original passwords for the accounts still work. I want to be able to change the permissions on these accounts back to administrator accounts but the OS won't let me since I do not have administrative permissions on any of the accounts that are on the computer.

 

If you boot into 'Safe Mode' you should be able to access the main 'Administrator' account, unless it has been deleted or corrupted. This account doesn't show on the login screen if there are other accounts present, so hopefully no one has messed with its settings. HTH

 

I tried doing that but it doesn't work since the account is limited to guest privileges