Hello all. This may be an old topic but I'm new to the forum and at wit's end. Has anyone had trouble with their 800's SD cards not being recognized by ANY computer? I am just short of 5000 shutter count and on my 5th card. When it happens no computer will recognize the card and best case I can USB files off the camera. Worst case the camera won't re-read the card when I put it back in. It has happened with SanDisk, PNY, and Sony 16GB SDHCs. Any info on this? Thanks, Gary K.