"Torrent Got Exception" error

[Mag99]

When I try to seed some shows overnight, I occasionally get a Bit Torrent error the next morning that says...

Torrent got exception: exceptions.KeyError
Traceback (most recent call last):
File "Bit Torrent\Raw Server_twisted.pyo",line 510, in_make_wrapped_cell
File "Bit Torrent\Connector.pyo", line 968, in connection_lost
File "Bit Torrent\ConnectionManager.pyo", line 459, in connection_lost
KeyError: 'M4-4-1--c38042f94f79'

This is exactly how the error message appears. Also, each torrent I have running has a yellow triangle with an exclamation point in it rather than a green checkmark, meaning the torrents are no longer uploading data. I highlight the torrent and force-start it again, but it eventually goes back to the same error message.

Does anyone have any idea what could be causing this?