Forums Bug Reports DCC Ports

It appears that mIRC is not always picking a listening port from the range specified in the options dialog.

Right now I'm helping a user to solve a DCC problem, and although his specified range is 2070-2090, the port number 2091 appeared in one of his DCC chat requests.

Please fix.

Related post

When I'm helping a user, this tends to happen because the user is doing something silly on his part, like networking (port forward/ virtual server) those ports locally instead of on their router or proxy terminal.

Ask the user to type: //say $portfree(2070) $portfree(2080) $portfree(2090)

He's done already, but next time I will

ill agree with that, i have helped people setup fservers standardly most ill tell to forward portsd 5000-5005 but sometimes mirc well use 5006 or 7, i checked on the fserver script, and it does just a standard dcc, every once and a while it exceeds the specified upper port. (while others are free within the range)

This should be expected to happen from time to time, when there are a very limited number of ports to choose from, and especially after having performed multiple sends. sockets take time to "cool down" before they can be used again, and if mIRC feels that none of these sockets are available it simply tries the next best thing.

You should also be aware that other programs might be making use of the ports you have selected for mIRC. Ports 1024 through 5000 are shared application ports, and should never be dedicated to the operations of a single application. I strongly urge all users who need to define a port range through their router or firewall, to select a range above 12000 and below 65000. This will both limit interference with other programs, breaking other programs, and will make it harder for someone to predict and intercept.

- Raccoon

That's quite normal, if mIRC is unable to use a port in the specified range for any reason, eg. if all ports in that range are in use or in a wait state, mIRC will default to using any available port.