Canon 6D Cannot Access SD Cards...HELP!

[eaphotography]

I've had my EOS 6D since 2014 with no problems until now. All of a sudden, every SD card I put in it (cards that I have used for years without any issues) is unable to be accessed by the camera. I can't format, update firmware, or take pictures. I'm afraid that something is going on internally in the camera that is corrupting my cards. I've tried everything I can think of and researched, including making sure my card is the correct format for the camera, but nothing is working. Has anyone ever had this problem and can you help me???

 

[Tronhard]

I would suggest doing a full camera reset and see if that helps.  It's the least intrusive measure.

[jdedwards]

Also, shine a bright light into the card slot and look for lint or debris. Some canned air blown into the slot may help.