After upgrading to El Cap from 10.6.8, my iMac doesn't recognize any SD card I insert into the SD slot. The cards do not show in Disk Utility either. I had to buy a card reader; hoping it works.
Oh my, sorry to hear that. I should get mine from Amazon this weekend, and if doesn't work I'll send it back if the postage is free. I regret having drunk the Apple Kool-Aid this time!