Today I encoded some vobs with avi.NET, then sampled them with WMP and was prompted to update my DivX codec to 6.8.5. Okay, I've updated several times in the past with no issue so I went ahead and did it. Then later I tried to do some more encoding with avi.NET and got the following error each time it tried to start the first video encoding pass:
I did a system restore to roll back to whatever I had before to resolve this (6.8 or 6.8.4 probably).