I guys, I am working on a program that does remote desktoping and I am finding the biggest issue is that most people have routers which block most ports.

What port do you recommend to create the least amount of difficulties with routers.

(This program will be used for technically assisting the technology impaired thus it must be simple :P)

PO

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You can choose a port from 0 to 2^16. Most windows services don't use port numbers past 10, 000.

Try to avoid using port numbers < 1024 unless for their original purpose. They are loosely called "reserved port numbers" because they are used for very specific purposes. Technically you can use them, but you will be blocking what might be an important service from operating while you do.

EDIT: I often use port 8080 for an http-style service as most routers will allow this by default, not that RDP is one but thought I'd add it as an example.

I tried 3389 (RDP Port) that failed, and yet Remote Assistance works.

8080 Also failed, and just for giggles I tried port 80 and it failed to and yet when I tried 6112 (A port I forwarded to play warcraft 3) and that worked.

I am so confused!

Post your code?

I've used port numbers before, I can't speak for the similarity of my assignment to yours, but I believe I used values that darkagn suggested with no problems. I pretty much just used the Java Sun tutorials on Sockets when I used ports. But post it and I'd be glad to take a look and if I can't help, someone will :) .

I tried 3389 (RDP Port) that failed, and yet Remote Assistance works.

Now that would mean the specified service is already using that port, so if a port is already in use, you application cannot use it for listening, have you tried turning remote assistance off.

8080 Also failed, and just for giggles

8080 is normally used as a port for intranet websites so many ISPs tend to block this port for receiving traffic from outside.

when I tried 6112 (A port I forwarded to play warcraft 3) and that worked.

Here you most probably did not have WarCraft running and thats the reason why I am guessing your application worked.

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