Just browsing around the site and came across this post, which is interesting because I have a similar issue: My card reader has no problem reading compact flash cards from my Nikon D70 on my Macbook pro (OS 10.4), and immediately mounts the disk image on the desk top, labelled "Nikon D70" and Photomechanic opens properly to import the files. Same behaviour when I plug the camera directly into the USB port on the Macbook. However, when I put an SD card in from my wife's Canon SD 630, the light on the reader comes on, but nothing else happens, doesn't mount, doesn't open PM. Similarly, plugging the SD630 directly into the computer produces no response. Loading the Canon software that came with the computer seems to be the only way to import the photos. So I wonder--is it something about the canon format on the card that the computer cannot read without the canon software? Neal, what kind of camera are you using?