avi clip works in clip window, but not in timeline window

This is Premiere 6.0 on a more-than-adequate machine, w/ XP. Yes, I have rendered it and saved it, but it is just a black screen with no audio.
I ripped the material from a dvd and converted it to avi. I tried different project settings and even re-ripped and re-converted the material all with the same results. What simple, brainlessly obvious step have I missed?