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Getting Blocked by Local Firewall or Anti-virus software The file C:\Program Files (x86)\Fantasy Grounds\FantasyGrounds.exe must not be blocked by your security software on your computer. Add an exception to your firewall or security software for this and any other exe files found in that folder. There have been situations where updates to popular anti-virus software has caused Fantasy Grounds Classic to suddenly become blocked. If Fantasy Grounds Classic usually works and suddenly stops, try temporarily disabling your security software to see if the problem is related to a recent update.
Link: https://fantasygroundsunity.atlassian.net/wiki/x/AgCrTQ
Multiple local Internet Routers Most routers hide everything behind the router for security reasons. By port forwarding TCP 1802 traffic, we tell the router where to send the traffic. In a 2-router situation, you have to port forward the inner-most router just like we describe above. Afterward, we need to then port forward 1802 TCP traffic from the outer-most router to the inner-most router to form a daisy chain.
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