Life in the woods has dulled my network skills or Networking 101

A beautiful day today. Nice enough that I took my bike on the hour and ten minute ride into work. Route 6 is a little bumpy and 395 is pretty windy but it was still fun and always good to double your gas mileage. So I am working at work, working along, as a worker, working in IT, as if my job, the job of IT. And of course at 4ish the fax client decides it doesn't want to communicate to the server anymore. It works on the server so I easily conclude that its a server issue. But for the life of me I can't fix it. Everything appears normal, the services are all running, I tried rebooting the server, checked event logs, checked DNS and that I was able to pin the server, turned off antivirus. We have support on the fax app so I call them. Do you know what they said? Is the firewall on? I check and of course it is on. I turn it off and it starts working. Ignoring the security risk of having no firewall on (although they recommend it, its an internal server, has Symantec security suite including IPS, etc) that should have been one of the first things I checked. Networking 101! The only firewall in the woods would be a wall of fire from a forest fire...