Problem with password on boot

When I turn ON my Dell desktop 3646, the very first screen I see (before I have made any entry) shows my name and displays the message "You have entered an incorrect password, try again." When I click "OK", a second screen appears with two entry slots; the first slot UserName "shows "801"; the second slot is labeled Password. When I enter my password, the PC completes its boot.

What is going on here? What does "801" mean?

Can someone tell me how I can eliminate this annoying sequence?

Thanks.