Remove Workgroup Password in XP

I've been searching through the Internet to fix my problem about Workgroup Password in XP. I want to remove the dialog asking for me to enter workgroup password while accessing one of the workgroup PC.

I have tried to enter the administrator password but keeps rejecting the request. It so annoying that I can't even share network printer or files on it sense I have no idea about the password.   I can access all units in the LAN except the one which  has the workgroup password.

Setup Details:
We have 18 desktop computers using Windows XP and we are all connected in a single LAN. File and Printer sharing is allowed. Our antivirus is Avast 5.0 Free Edition and Almost of the units with Intel Dual Core Processor. We have internet and LAN connection

I have done the following steps and I have fix it:
 1. Enable All File Sharing Menus
    a. Go to Control Panel > 
       >>Network Connections 
        >>Right Click Local Area Network > 
                  1.Put Check to File and Printer 
                   2. In the Firewall Menu go to Exceptions Tab Enable all Menus

  2. Admin Tools Configuration. 
     >>Control Panel
      >> Administrative Tools
       >> Local Security Policy 
         >> Local Policies
          >> Security Options 
            >> double click Network Access: Sharing and Security model for Local Accounts
              >> Change to Classic value
                  >> Then, Close all 
                     >> Shutdown and On your PC.

         .Remove Deny Access value
           >>Control Panel >>
            >>Administrative Tools 
              >> Local Security Policy 
                >> Local Policies
                 >> User Rights Assignment 
                  >> Deny Access to this computer from the Network 
                    >> Delete Guest Value
          .Check the Guest account status
              >> Control Panel
               >> Administrative Tools
                >> Local Security Policy 
                 >> Local Policies 
                   >> Security Options
                     >>Accounts: Guest account status 
                      >> Enabled ( if disabled, it prompts you for workgroup password)

After I have done some of the steps above I am able to remove the annoying password dialog and I am able to access the printer attach to the unit.

Not working? Please put your reactions below and let's discuss!