Automatically Logon
After updating Windows XP manually or via Automatic Updates, you may notice that Windows XP no longer logs into your account automatically. This is caused by the .NET framework update, which creates an additional user account named "ASP.NET". However, there is no need to delete this account or to remove the installed update. You can easily configure Windows XP to automatically login by using the following tweak:
Click "Start" -> "Run..." and enter "control userpasswords2".
In the following window select the user account you want to log in automatically. Then uncheck the box labeled "Users must enter a user name and password to use this computer".
Click "Apply". Now enter the user account password and close the dialog by clicking "OK".
When using Windows XP Home Edition, don't try to auto-login as the built-in Administrator, as you will receive a restrictions error!