unknown port 137 from GP users to Public IPs

[SThatipelly]

         I have GP users whose logs show multiple attempts to public IPs on port 137. I have checked this KB https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClLfCAK and made sure user-id is not enabled on Internet interface but I have it enabled on GP interface.Image above shows the NBNS pcap captured on firewall.Anyone experiencing this?

[jdelio]

If you are seeing port 137 traffic from GP machines to Public Internet IP's then it sounds like the machines are trying to use netbios for file sharing or something else is going on. 

Are you allowing port 137 (or 135-139) thru the firewall to the Internet?