If a client cannot join a session then it could be that the port is blocked, maybe by the isp. You can re-map the port by following the instructions below.
Changing the default hosting portThe host can change the default port for SOW by changing the value in the SOWWL ini file. You can change the default 31791 to another value and let the clients know. The host will also have to have the new port forwarded in the router/firewall.
Location of file: C:\Users\Username\Documents\SowWL
File name: sowwl.ini
[variables]
$gameport=31791
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