Secure Windows XP2 on Netwrok

start->Run->type regedit->
now regedit panel gets opened
HKEY_LocalMachine
System
Current Control Set
Services
LamManserver
Parameters

Now you should add two more DWORD Values
create new dword value  

Name                  Value
Autoshareserver    0
Autosharewks       0

close all panels->restart the PC