I've run into a few problems recently with my PCH and wondered if the problem was related to an recent upgrade Essentials did. I still am not sure but for me, I just changed the port to a different one and it worked. So, if it worked for the new port, why not the old?
For what it's worth, I have my firewall set to enable. I think, but am not sure, that when you install NPVR, it sets the firewall exception.
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