On My Family XP machine I had five profiles (my own, wife and kids) I switched to BT broadband and removed MCaffe anti virus and installed Norton anti Virus.
My own account works fine, but all the other accounts appear able to login, but once logged in the following symptoms occur.
No access to internet, not know in BTbroadband login, cannot change desktop settings, machine does not remmember last used programs, recent documents only contains items used before upgrade, Word cannot save documents, save as does not show expolrer dialog to choose location and filename......
It is almost as though, even though the users exist (thay all have administrator rights) the system does not recognise them once they login.
A new user (created since the upgrade) seems to work correctly.