Failed to connect. unique error message

Whenever my friend tries to connect to my server, my cmd terminal gives the messages: Failed to send raw data to client: A blocking operation was interrupted by a call to WSACancelBlockingCall, and Failed to send raw data to client: An existing connection was forcibly closed by the remote host. My other friend has no problem connecting. Port is forwarded correctly. any help would be appreciated.

His system is blocking traffic from the platform, he needs to adjust his firewall settings to allow all traffic from BeamMP.

He tried just turning firewall off completely and it still didn’t work, any other suggestions?

@Protogen_1 You got anything for this one? Firewall is like my go to for this error.

Get your friend into this thread instead.

Don’t turn off the firewall it isn’t going to help.
If it doesn’t work on any other servers as well, create progrram rules for the BeamMP-Launcher.exe in outbound