Christy, that is a very strange thing to happen. It seems that your 'User' acccount has been locked out. I am not too sure. If you can log in with the 'Administrator' account, go to Administrative Tools-Local security Policies, and take a look at the account lockout duration. What does it says ? 1 minute, 30 minutes or more ? You may have to wait out that period. 
-- but try to change it to '0' and see whether you can get back your accounts. Maybe David or Bob can share more information.
My OS is WinXP Pro SP1
I have a user account with administrator's reghts named "User" At the log-in screen, this account and the 'Guest' account (which is off) shows up.
Recently, I tried to go into the Administrator account to see if I have one, so I keyed in ctrl=alt+del twice at the Welcome screen. The Administration account log-in came up and I was able to log in, without a password, and went to the default desktop. I logged out and shut down. On booting up the next time, the Administrator account came up at the welcome screen for me to log on-- the usual 'User' and 'Guest' accounts were missing--i.e. I was only able to log-in as the Administrator. Of course, I was sill able to access my documents via the Administrator acount. What is wrong ? How do I now log in as 'User' ? Thanks.
christy.
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