In Chromium 37.0.2062.120 ongoing downloads are canceled when errors occur, e.g. when you stumble over your network cable, unplug it from the PC and Wicd subsequently tries to establish a wireless connection. In such cases Chromium displays an „Unknown network error.“ message in the Downloads manager.
This shouldn’t happen as by canceling the download the data downloaded so far is being deleted.
Instead, Chromium should only pause the download upon error and wait for user interaction to cancel or resume it.