How can I remove XP CPU Login on boot

A friend of mine has XP-PRO Corporate w/SP1 on his desktop.

He doesn’t use a PW to logon, but the Logon Box comes up on boot.

How can he remove this so it will boot up all the way without having to click “ok” or “Enter”???

He tried assigning a password (then re-booted and then removed PW and re-booted again)with no luck???

Will installing SP2 correct the problem???

Thanks

charletshew