Home Network Problems Please Help

[moxons]

I have recently lost the ability to view my shared drives and printers on my main PC from both my laptop and through my sons PC in his bed room
I can still access shared drives on my sons PC through mine
The internet sharing still works from my PC to others on the network

More info

Cable modem & 2 10/100 network cards on my main PC and shared internet access
5 port Hub

Windows XP pro on all machines

When I search for my PC from my son’s PC I can see my computer but when I try to explore it I get a message “\\***mypc is not accessible . You might not have permition to use this network resource contact network administrator to find out if you have access permissions. Logon failure the user has not been granted the request logon type at this computer “

I seem to have tried every thin in the help and support section from changing computer names and workgroups to changing network cards all with no effect
:rtfm [COLOR=Cyan]

Please help

[tomtx500]

turn the fkirewalls off on all the machines, then go into the dos prompt and type ping whatever each of the ips are. Now to turn the firewall off go to start network and then your connection and turn off firewall. then when u ping after it should work. had the same problem. thats the xp firewall i amtalking about by the way,and any other software firewallls need to be configured for networking.