My CF card never mounts in Finder, disk utility, the desktop or in image capture. I'm not 100% sure about this but it seems to have shown up after I upgraded to Lion 2-3 weeks ago with the iOS5 release. Aperture will show the camera and CF card but only lets me import (random # of photos) then it fails to import the rest. I have to quit, re-open aperture or turn the camera on and off to get all my photos loaded. I can not understand why this is suddenly giving me all these problems. The card works perfectly in the camera so I don't believe the cards gone bad. Using a Canon 50D and Kingston 16gb CF card. Thank you to everyone who helps.