To enable automatic logon for a Windows XP Professional domain member without editing the registry:Use TweakUI from the Windows XP PowerToys.
To enable automatic logon for Windows XP Home Edition or Windows XP Professional (non-domain member) without editing the registry:1. Start / Run / control userpasswords2 / OK.
2. On the Users tab, clear the Users must enter a user name and password to use this computer box.
3. Press Apply and OK.