suppose you mean a result that reports an "error" or "invalid"? Multiple causes, you mention a few, can turn your WU into GOOH, including hickups during transmission, when the checksum does not match the completed WU transmitted (very unlikely). Hardbooting your PC/Laptop definitely falls in the cagetory of hi potential disaster. If you can plan it, best is to properly close BOINC or UD agent, check if any remaining processes can be seen in Taskmanager, then proceed to close.

I must say, with UD & BOINC i rarely had issue long as i properly closed thru the windows closing procedure. Both programs safe the WU every somany seconds / minutes, and pick up from there when restarting....you might observe the counter skipping back 7 to 10 minutes (even half an hour in UD).

I'm sure the FAQ's give some advise for either BOINC or UD how to best go about it....in my specific case, empiricals taught me what to do and not, broadly described above.

ciao