I download the AVI file produced by the Snagit extension on my Mac. When I try to use it, all I see is a black screen. I import the file into Adobe Premiere and it tells me "The file has no audio or video streams."
I believe you'll need to convert the .avi to a different video file type to be able to open it in Adobe Premiere. I'm not too familiar with Premiere, but converting it to an .mov or .mp4 format should work.
Thanks. That's pretty much what I figured. I was able to use "Smart Converter" to get an MOV file that Premiere accepted. However, that same MOV file would not open in QuickTime Player: "The file may be damaged or may not be a movie file that is compatible..."