If you want more flexible control of file and printer sharing on your networks (for example, uni-directional NetBIOS traffic), you can do the following:

1. Allow file and printer sharing on other LANs (Local Area Networks) than those in the LAN settings list. This allows NetBIOS traffic on those LANs to be processed by the firewall rules.
2. Create high-priority global rules which allow communication to/from hosts with the appropriate NetBIOS ports and protocols. We recommend that you create global rules to explicitly block all unwanted file and printer sharing traffic rather than let it be handled by the default rule.

To allow file and printer sharing on other LANs than those in the LAN settings list: