Whilst downloading a file, the progress meter said 99% (whoopee, me thinks almost done) only to find that after a few minutes it reads 84%. Twice this has happened to me, how a can a progress go backwards? I'm so frustrated as it has taken soooo long to get where I am with this particular file, nearly 2 weeks.

bad part of the file; piece was dropped. Hashing should be implemented in the future and will help fix that.

A bad segment was dropped by XoloX (after a crc check) when doing multisource downloading. if you leave the file.. it will eventually finish and if it drops enough bad segments will change to 'safe download' mode in which it then only tries to get that file from a single host.

And if the dropped downloaded part business is still driving you crazy…
You could try un-checking the box that says “Drop and retry incorrect downloaded parts”. You run the risk of getting a corrupted file, but in my experience the risk is minimal.

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With Desperation comes Inspiration.

The "Drop and retry incorrect downloaded parts" suggestion, Like markywrol said you run the risk of getting a corrupted file but the option *is* there because he is right.. the risk can be minimal but that is for you to decide and test for yourself

^^^ markywrols's suggestion is in Tools > Preferences > Downloads Tab (shortcut: alt+P)