dont worry this port (6346) is the LISTENING port for your side of the host which means that u tell the other gnuttella hosts to talk to u through this port.I use 6347 cause i thought if anyone is trying to hack me based on the fact that i use gnuttella he is going ot try 6346 first, and i never had any problem using that port. It should be ok if u put 21 or 00001 9999 provided that the port u will put there is FREE. How u can find that out... hmmm i used sisoft sandra but there must some program outthere to tell u that...