Client/emulator connection dropping

Hi guys, so basically we've setup an emulator (Phoenix 3.11.0) as we want to run R63, the emulator loads fine and I and others can get on the client just fine, but when a certain person tries connecting to the client, their connection is dropped by the emulator.

We thought it might be something to do with the PHX license files or something, but we cannot find a solution to why his connection keeps being dropped by the emulator

the emulator:

https://forum.ragezone.com/cache.php...%2F33thz45.jpg

post config, client and external variables

Try this, posted it for another guy but you seem to have the same issue.
https://forum.ragezone.com/f333/gte-...5/#post8510172