Hi there
I had been using qbittorrent for Windows, and was very impressed by its speed as well as the utorrent-like look. I decided to take the plunge and start adding torrents I had been seeding to private trackers.
Most of these were checked and subsequently seeded fine. However, I also had some very large torrents in which I had only selected about half of them to download in my previous torrent software, and I simply wanted to seed these torrents. It wouldn't allow me to add a torrent without specifying at least one file to download (which seems like a bug in itself to me, as I just wanted to seed the torrent without downloading any new files), so I chose one of the files I had already downloaded assuming that during the initial check it would see all the other files I had also downloaded, allowing me to seed these files. This is the behaviour in Vuze, uTorrent and Deluge. It looked like it was going to take quite some time to check the existing files in this torrent- so I left it to do its stuff.
You can imagine I was pretty horrified to see that, when I came back, 100GB worth of files had disappeared from the torrent! After my initial outburst to my computer calling your software every curse under the sun, and proclaiming I would never use this program again, I decided I would first try to at least help you guys out and let you know, or file a bug report or whatever. I also much preferred using qBittorrent over any of the other bloated Open Source torrent programs, so if this could be fixed I could definitely get back to using it. I tested if the same thing happened with a (much smaller) torrent in the version provided in the Ubuntu repository- and the same thing happened.
Hope this helps
EDIT: Just found the missing files in a .unwanted folder in the root of the torrent's file. It seems quite a bizzare way of handling these files in all honesty. Is qBittorrent confusing the priority of "Do not download" with "Delete" for files? At least they were moved rather than deleted for good!