Hi all, 
Hope someone can help me with this one, I'm working on a project that I need to finish quite soon. 
I am creating a soundtrack for a client on top of a video... so far so good! 
the video he sent me last week is loading fine in Sonar and I can work with that, today he sent me a new render of the video which contains more specific details I need to do my work. Same video format but now when I load it to sonar I can't see any thumbnails and the video screen is all black. I tried converting the video to AVI and now when I try to import it, the whole computer freezes.
 
 

How old is your hard drive ? Do you have up to date video drivers installed ?
How are you importing the video ?

My Hdd is literally 3 Days Old, just installed a SSD. Codecs should be fine as I cloned my Hdd to the ssd. I just import the vidéo from the file - import vidéo menu. Both vidéos are mp4, The first one Works just fine, the second isn't. I realised that the second one has a larger résolution.
The second vidéo won't work in Windows media player either but Works on vlc. Tried to Read it in windows media player on an other computer and it works... Just asked the client to send me another render with the same resolution, standing by...

It's entirely possible that the second video was corrupted somehow. Also, if the second video was of a higher resolution, you might be need to reduce the resolution using your video converter software.