Although you can log in locally without a password, by default,
Windows XP Pro does not allow network users to access the computer
without a password. Typically you will receive an Unknown error 31
if this is the case.
To change this setting:
- Click Start -> Run and type
- Go to Computer Configuration/Windows Settings/Security
Settings/Local Policies/Security Options
- Double click on Accounts: Limit local account use of blank
passwords to console login only (see picture 1).
- Disable this option.