Configure Windows XP to Automatically Login

Click Start, Run and type CONTROL USERPASSWORDS2, and click Ok.

Select the user account from the list (the account to which you want to automatically logon).

Uncheck Users must enter a user name and password to use this computer option, and click Ok.

Type the user account password and complete the process.

For Windows XP Home, don't try to auto-login as the built-in Administrator, as you'll receive an error message.

OR

Automatic Administrator Login
Well here's the trick which you can use to prove that Windows XP is not at all secure as multi-user operating system. Hacking the system registry from any account having access

to system registry puts you in to the administrator account.

REGEDIT
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"AutoAdminLogon"="1"

or

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