Can the author please send me an exported version using H.264 video codec

Seems as thou I am having similar problems as other clients are having with movies. My computer guy asked me to ask you this question in the subject line. I have no idea what this means. I sent him a video, he has sound but no video, and he has tried multiple applications, but the results are the same. No video. So, I am suppose to ask the author to send you an exported version using H.264 video codec???? Please help get this resolved!