It seems, given the tests below, that S_FALSE is returned if the graph can't seek (i.e. it's translated from E_NOTIMPL). In that case it'd be better to key this return value on the return from AddMediaStream() above.
Thanks for the review.
Sorry if I'm misunderstanding you, but I'm pretty sure the earlier AddMediaStream calls succeed under windows server. I believe the issue is that decoding AVI files isn't supported under windows server (I read something to that effect a few days ago, though for some reason I'm unable to find the link now).
Would adding an extra test (like IAMMultiMediaStream_GetInformation) to see if AVI files can be seeked be alright?
Also, a bit of a nitpick, but I think that duration would be more readable in decimal.
Good point, will fix.