My son has the Torch and I've got the Bold 9780 - he recently sent me a video clip he took via BBM. The msg gave me an option to 'accept', which I duly did -but then the downloaded file showed up as 0.0kb (which presumably means it didn't download).
However a file of some sort went into my video folder -but when selected says "The media being played is of an unsupported format" - so doesn't play anything.
Is it something he's done wrong - or is it something I've need to sort out in my phone's setup.
Best thing you can probably do, is to, Plug your BB Via USB & Get the video from your BlackBerry. Then Comvert the file to an MPEG-4 Format using a converter such as Any video converter. Then dump the video back on to your BlackBerry. That should work. If not, Ask your son to re-send you the video.
My opinion, I suspect the video download on your BlackBerry from your son's BlackBerry was interrupted or somehow failed. Or it failed on your son's end. That's why you see the file name but with a size of 0k, and why it won't play.
I would experiment. Have your son send it again, and watch the download on your BlackBerry after you accept. See what you see. I'm guessing it fails almost right away after you accept. If you get an error message, note it. Also, ask your son what he sees on his end.
I've done this with pictures and music over BBM between me and my wife's BlackBerry. If I ever had a failure it didn't make an impression on me. (But there is a size limit. I have tried to send files that were too large, and gotten an error message accordingly.)