Why is Bidirectional Encoding greyed out?

[Xlipse]

I can't, for the life of me, figure out why it's greyed out in VDub.. I've reinstalled all the typical codecs.. I can't think of why else it'd be greyed out..?

Help?

[fccHandler]

Hello again! :D

As I said in the other forums, you have to purchase the DivX codec to enable B-frames. Alternatively, you could get the ad-supported version and disable the Adware (see here (http://forum.doom9.org/showthread.php?s=&threadid=19583)).

[Evil Andy]

You may also have a profile enabled which doesn't support b-frames. Make sure you don't have a profile selected.