[SOLVED] Cannot connect to minecraft server without using a VPN.

[tjrelyts]

So my friend setup this minecraft server for my friends and I to join. He has done this multiple times in the past using the same IP, but this particular time I am unable to connect with my computer. I've tested this on a second computer on the same network and it did not work. When I enable NordVPN, it changes my external IP like a VPN does and I am able to connect. I am unsure why this is suddenly the case, but it is very inconvenient. On my Xfinity router portal I have changed the firewall to Low Security. I was able to get in once, but then I couldn't get in again on Low Security. If anyone has any solutions or input, that'd be greatly appreciated.

EDIT/UPDATE I left the server with the VPN on and now I cannot reconnect even with the VPN on.

 

[bill001g]

Run tracert to the server IP and see where it gets blocked if anywhere.

In general if it goes any place it is not a simple ip block. It would be highly unlikely something is blocking just 1 port you could have them change the port number and see if it makes any difference.

If it was actually being blocked by the network it would be much more likely on the far end.

I am going to bet this is some problem with the program itself. You can test it with a telnet command and use wireshark to see if you get syn-ack packet back in response to the initial syn packet. It is too complex to explain this in detail so lookup those term. Otherwise maybe uninstall and reinstall the game maybe will clear any issues.

 

[tjrelyts]

Run tracert to the server IP and see where it gets blocked if anywhere.

In general if it goes any place it is not a simple ip block. It would be highly unlikely something is blocking just 1 port you could have them change the port number and see if it makes any difference.

If it was actually being blocked by the network it would be much more likely on the far end.

I am going to bet this is some problem with the program itself. You can test it with a telnet command and use wireshark to see if you get syn-ack packet back in response to the initial syn packet. It is too complex to explain this in detail so lookup those term. Otherwise maybe uninstall and reinstall the game maybe will clear any issues.

So I did tracert. It seemed to trace it all back. I then did telnet coupled with wireshark. I checked the initial SYN packet and the transmission ended with a TCP Retransmission. So there was no SYN-ACK packet response to it. It seems to not be able to reach it. I also reinstalled the application, but that did not solve it either.

 

[bill001g]

That makes it hard since you can't tell where the packet it actually being blocked. Maybe try to disable the firewall on the pc but I doubt it is that. In general a firewall on a router does not block outgoing data.

>>>edit maybe I should be sure you telnet to the port you are testing not the default telnet port.

 

[tjrelyts]

That makes it hard since you can't tell where the packet it actually being blocked. Maybe try to disable the firewall on the pc but I doubt it is that. In general a firewall on a router does not block outgoing data.

Hmm. I have disabled firewall and it does not work. I also did telnet to the port (25565) with the server IP. I'm honestly not sure what is wrong. It seems to be a really obscure problem. I can connect to other servers seemingly fine. Generally, my friend has to allow our IPs through his router through the Xfinity XFi portal. However, while the rest of the clients' IPs go through and are recognized as trying to connect, my IP fails to even show up in his attempted connection list. I'm considering resetting my PC entirely, but I'm not sure that will solve it.

 

[bill001g]

You could boot a linux image and then try the telnet trick