Blank Password Network Access
Windows XP professional will not allow network users computer access without a password. Trying to do so will normally return and error code. To allow network access using a blank password:
[Start] [Run] and type gpedit.msc and click [OK]
Navigate 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
Select the radio button next to Disabled and click [OK]

- srikanth dhanwada