Sorry its been so long folks! I really have a lot to publish, just this thing called work gets in the way....
OK, you have just applied a hotfix, a service pack or did a backup and while you can get to everything just fine, there are a few administrative duties you cannot complete, namely adding new user permissions. You can get to the permissions area, you can browse your address book and enter people but you cannot click OK..check your site lock
Stsadm to the rescue again!
stsadm -o getsitelock -url http://sharepointurl
If it comes back locked...unlock it :)
stsadm -o setsitelock -url http://sharepoint -lock none