Yes, you need to use the Switch to dir button and set a different drive manually. ffmpeg.exe comes with the server and it seemed to work ok with xp. So if your knots folder is on c:\, use c:/knots/win32/ffmpeg.exe as the path. If you got win32-popen3 installed, it should work. But I don't have Vista so I can't be sure if it needs additional gems. But I've seen Knots work on Vista so it should be possible Anyone got it working ok with Vista?