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Just for a little background info I have 2 computers set up and I use torrents to easily transfer large amounts of data between the 2 PC's often, or should I say, computer a to computer b. On computer A I have windows 7 and am using uTorrent 3.0, the ports are properly forwarded and configured to this machine, no problems transferring data from A to B. Now on my Desktop, which will be referred to as computer B, has xubuntu set up on it and uses qBittorrent 2.8.4. The ports are properly forwarded and has no problem seeding 200+ torrents over a private tracker. But it cannot transfer data over LAN, oddly enough, and I can't for the life of me figure out why. I am using the http://[IP]:[PORT]/announce format as my tracker, which works fine to get data from computer A to B, but it cannot go vice-versa B to A.

I'm at a complete loss here as how to solve this problem!