File/Render As......
Then be sure that Save as Type is set for "Video for Windows (avi)"
then on that same sheet click Custom
then go to Video tab (at the bottom)
In "Video format " drop down list are all your codecs
fultro
i did have ace mega codec pack but uninstalled that some days ago, i do have other codec 'programs' i guess you could call them, like ffdshow/ ac3 filter/divx and xvid. I'll try reinstalling vegas ans see what happens.