many tried but nobody has every found out what exactly causes divx3 - codec errors. on some systems/installations you get 'em, on some you don't - there is nothing you can do to change that. usually you get them always or never. there are two different kind of errors: 1) freeze frames: playback stops at such a frame. (there is a tool to fix that after encoding is finished) 2) "shit": completely ruined picture until the next keyframe. nandubs "anti-shit" is the only way to "avoid" these problems. actually it can't avoid them, it just tries to detect when it happens, then reencodes the problem frame as a keyframe. whether "anti-shit" is able to handle these errors and still keep the desired filesize obviously only depends on HOW OFTEN the errors occur (and that depends on your system, the source material you are trying to encode, the bitrate,...). "anti-shit" can help in many cases, but not in all - and unfortunately it's very slow. if you get lot's of errors i feel sorry for you and recommend to use xvid or divx5. wef.