The Norton Anti-Virus firewall is actually quite simple to configure to allow Windows filesharing. Follow:
1. Click the "Configure" button for Personal Firewall. This will open a new window.
2. Go to the "Advanced" tab and click on the "General" button.
3. Another window should open with a list of rules. About halfway down the list, a rule entitled "Block Windows File Sharing" should appear. Click on it and click the "Modify" button.
4. Another window should open. Select "Permit" in the Action tab. On the Connections tab, select "...to and from...".
Click OK out of all the windows. If you need any more help, post again.