I used Any Video Converter( found on
www.tips4pc.com), I tried to convert the sample videos from my PC to MP4 format and onto my NOOK color. I never got an error message, but it wouldn't open for me. I have a Micro SD card inside of my NOOK color and it recognizes it and the information on it(music, etc). I copied the sample video onto the SD card but it wold not open or play for me.