Question

I am developing a windows service application that listens on port 63639
and can get messages an retrive messages

When I do this in the cmd

  telnet 127.0.0.1 63639

it get inside and get back the welcome message

but I want to communicate with this application from another computer on the local area network

I have 3 computers on the network with a d-link dsl-2650u router.

My ip address is 10.0.0.3

When I try the cmd:

 telnet 10.0.0.3 63639

from another computer I receive “could not open connection to the host, on port 63639”

Then if I try:

 telnet 10.0.0.3 80

I am able to get access. I also tried port 135 and that is able to get access also.

That leads me to think the blocking is from my router because I have win 7 and I looked in the firewall logs and I can see the logs for ports 80 and 135 but not for port 63639.

I am very sure that is the router. I also set the router for NAT/DMZ for 10.0.0.3 and it still does not work and I am not able get any log. I also tried defining NAT/Virtual Servers.

Thanks guys, I am going crazy since I have been trying to get it to work for over 6 hours

Answer 1

If you bind to 127.0.0.1, you’ll only be able to connect from 127.0.0.1; if you bind to 10.0.0.3, you’ll only be able to connect from devices on that network interface. If you bind to 0.0.0.0 you’ll able to connect from interface the computer has.