I have a project for which a color version (encoded H.264) plays perfectly on You Tube. I have encoded a version in Black & White and uploaded it (H.264 again). The file plays perfectly on my PC (so let's assume I have not uploaded scrap...)
All I get once on YouTube is a corrupted video (can't see anything while video is running. Audio is OK though).
I uploaded it a second time, in case it might have corrupted during upload : same result.
If this can add for an explanation :
1) Original project is done under Premiere CS3, exported (H264 codec) via AME CS3. This version is ok on You Tube.
2) I have then reimported the resulting file (in QT format) as a new project in Premiere CS4. Made the edit to get in B&W. Then exported that project using AME CS4. Here, the resulting QT video has about the same size as the original output under CS3, and it plays correctly on my PC. It is once on You Tube that it becomes unreadable.
Any idea ?
I have then reimported the resulting file (in QT format)
Don't do that. Never use a compressed delivery file as source for further editing. Go back to the original project and work with the original media.