“Card cannot be accessed. Reinsert/change card or format card with camera.”

[laithai]

This issue happen on my 600D, I cannot format in the camera and the card cannot be found in my computer.
The others card still working great. I use this card just 2 months. Is there any way to solve this issue or I have to throw it away.

 

[KmH]

Is the card locked? There is likely a little locking switch on the side of the card.

If the card is not locked, not being able to format the card makes it useless.

If you have the tools and other gear/parts needed you could try taking the card apart and change out the controller chip.