Hi, I hope someone may have the answer to this rather urgent issue. suddenly after a year or two of Sony Vegas HD 11 working perfectly a video I made last week won't play the captured m2t rushes that did play perfectly when I created the project. Audio plays but video neither shows on the timeline or in the editing window. The video runs in media player outside Vegas no problem

I have also tried a clip from a previous video and that does not work inside Vegas

However it all works perfectly on someone elses installation of Vegas.... help please
thanks so much
Andy