When exported, I only get sound, and the video is blank.

[Guest_imported]

I have checked all the settings, and made sure that they are all correct in order to export video files. I have tried exporting, using different codecs and different applications (i.e: .mov .avi etc),
but still, i only get sound.

Premiere exports other avi files ok, but not footage that i've captured.
However it was exporting these captured files ok a few days ago.

Please Help!