I have used quicktime Pro for a couple of years somewhat successfully. I recently upgraded to hd video cameras. My agency insists on .mov files as a condition of acceptance. So, I bought (or was forced to buy) apple's mpeg codec. I also downloaded the newest version of Quicktime itself. When I installed it and tried to convert some mpg files (HDV 1080i - 60i) I got "Error -2048. Could not open the file xyz because it is not a file that Quicktime understands." So I decided to try mpeg streamclip, which requires that I uninstall quicktime. The website also requires the the mpeg stream clip be an older version for installation (?). As I began to uninstall Quicktime, I began to get popups saying I that if I continued, I would loose the software that I had spent money on. I would be willing to spend some money on a program that has licensed this from Apple as long as is was shareware so that I could try it first. Unfortunately, this is the type of thing that is going to happen when the marketplace insists on a closed proprietary system for an industry standard. Any suggestions? My system is a an almost new custom pc with an Intel duo cpu running Windows 7 with 4 gigs ram.