There's a compatibility issue (aka bug) when DivX6 encoder is used from VirtualDub or VirtualDubMod. Short description (so you can tryout by yourself):

1.From VirtualDub select DivX 6.1.1 Codec (=latest version) for compression.
2.Configure the Codec by selecting Video tab.
3.Enter 32 for crop left and 32 for crop right (other settings doesn't matter).

4.If VirtualDub didn't crash till now, confirm with OK.
5.If VirtualDub didn't crash till now, try to convert your source file.
6.VirtualDub should crash till now, showing some kernel32 error message.

This, of course, doesn't happen when DivX5 codec is used, so it could be DivX6 bug...

Now exit Configure codec in Virtual dub (but you may keep VirtualDub open):

1.Open the registry [HKEY_CURRENT_USER] and find:
Software/DivXNetworks/DivX4Windows/State
2.For above Codec you'll see here the entry:
06_01_01_01031_Tiger_WinCodecArtwork
containing last valid CLI values like:
-bvn1 1000000 -vbv 4854000,3145728,2359296 -c 8,16,40,40...
3.In this example, values "-c 8,16" define crop area (8=left, 16=right).
4.Now you manually change only those values to:
-c 32,32 (leave all other values unchanged)

Now again, in VirtualDub open menu Video>Compression... and try to select DivX 6.1.1 Codec -VirtualDub can't find it anymore! If you restore values in registry, VirtualDub will find DivX6 codec again.

So... where's the bug?

Greetings,
Bogdan

PS: I'm not a member of all possible software forums (to post "official bug report"). If somebody has time to proof above issue, please give a notice to appropriate forum. Thanks