Client isn't receiving UDP packet from server.

Question

Working on a C# app, have been trying to debug this for hours. It appears the client sends a packet to the server, the server gets it and replies, but the packet isn't being sent to the client. I use the IPEndPoint to send it back to the client, but it still doesn't send it to the client, I'm at a loss. (I have my network configured to allow UDP packets to pass through the port 13044 and 13043, the ones I'm using to listen and send. (13043 the server listens on and 13044 the client listens on.))

Answer 1

Hi @CakeDev ,

Have you tried using a tool to capture UDP traffic on both the client and server machines?

Make sure the client is indeed listening on port 13044 and the server is sending to that specific port. If the server’s IPEndPoint is somehow off by a port number or IP, the packets won’t reach the client.

Also check the firewalls and routing. Even if the ports are allowed, sometimes specific firewall rules can still block packets. Temporarily disabling the firewall can help rule this out as an issue.

Best Regards.

Jiachen Li

---

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.