firewall blocking home network

>Hi,
>I'm having a couple of issues involving my home network with 2 computers. My
>main computer has vista with Norton360 and my notebook computer has XP with
>NIS2007. The main computer can see the notebook computer in the workgroup and
>the notebook can see the Main in the workgroup. Now, the Main computer cannot
>access the notebook computer unless I have Norton firewall turned off the
>notebook. The notebook computer can't even access the workgroup unless the
>firewall is turned off. I was wondering if anyone knew what setting in
>Norton's firewall needs to be changed to get these computers able to talk to
>each other all the time without having to turn off the firewall on my
>notebook?
>
>The second issue I'm having is when I have the firewall turned off the
>notebook, the Main has access to my notebook but when I try to access the
>Main from my notebook I get a message saying that
>
>"\\Main is not accessible. You might not have permission to use this network
>resource. Contact the administrator of this server to find out if you have
>access permissions. Logon failure: user account restriction. Possible reasons
>are blank passwords not allowed, logon hour restrictions or a policy
>restriction has been enforced."
>
>I tried turning off the firewall on Main but still get the same message. Why
>can't I access the Main computer from my notebook?