losing users, changing users, multiple logons

[TwoMoon]

WinXP Pro

I have four xp machines. There can be numerous users at these machines, however typically at two of them is the same user every day. I added addtional users in the case that these two "normal users" were ever out sick. Well, when I went to add users or change existing users on these machines, I somehow lost the user settings for these two normal users in the process. Now when they sign on, their desktop settings are gone. Their user folder is in Windows Explorer but instead of signing on to that user profile, it seems WinXP has lost the connection between it and their Novell login and wants the users' full name for the WinXP login versus their initials like before. I am so totally confused as to why this happened. I've tried deleting the new profile with their full name and logging them back on with their initials but WinXP doesn't recognize them. Is this something in the registry that I need to fix?

Thanks in advance.