From the Deployment Tools documentation found on the XP cd:
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Syntax
AutoLogon = Yes | No
Values
Yes
Configures the computer to log on once with the Administrator account.
No
Does not automatically log on to the computer.
Comments
The entry is not valid on upgrades.
When you set AutoLogon to Yes, you cannot log off. If you try to log off, you will be logged back on automatically. The only way to log off is to reboot, which decrements the value of AutoLogonCount.
If you specify a password in the AdminPassword entry, Setup uses that password when you log on automatically to the computer. After the installation finishes, Setup deletes the password from the copy of the answer file left on the computer.
Important- Encrypting the Administrator password in the EncryptedAdminPassword entry disables AutoLogon.
- To skip Windows Welcome, set UnattendSwitch to Yes in the [Unattended] section of Unattend.txt.
- If you wish to log on automatically after running Sysprep in Factory mode, set AuditAdminAutoLogon to Yes in the [ComputerSettings] section of Winbom.ini.
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(Relevant section: "
Encrypting the Administrator password in the EncryptedAdminPassword entry disables AutoLogon.")