Upgraded 10.9.1 to 10.9.2 now SD cards not recognized On early 2011 MacBook Pro 15inch -- I use the SD card slot a lot. Suddenly after the upgrade to 10.9.2 (for security reasons), now inserting an SD card gets no reaction, instead of showing an icon on the desktop for the new mounted volume.
try another brand of sd card, I had this problem with sandisk cards but al others would work perfectly.
You can also try wiggling it around a bit after a while it would read my cards if I did that.
Just don't break the card ;)