Canon EOS 5D MARK III Instruction Manual page 57

Troubleshooting Guide
The lens cannot be attached,
® The camera cannot be used with EF-S lenses (p.39).
The viewfinder is dark.
® Install a recharged battery pack in the camera (p.28).
No images can be shot or recorded:
® The card is not properly inserted (p.31).
® If you are using an SD card, slide the card's write-protect switch to the
Write/Erase setting (p.31).
® If the card is full, replace the card or delete unnecessary images to
make room (p.31,277).
® If you try to focus in the One-Shot AF mode while the focus
confirmation light <O> in the viewfinder blinks, a picture cannot be
taken. Press the shutter button halfway again to refocus automatically,
or focus manually (p.44, 111).
The card cannot be used:
® If a card error message is displayed, see page 33 or 371.
Anerrormessage d sp ayed w hen thecard nserted
another camera,
® Cards with capacities greater than 128 GB are formatted in exFAT.
This means that if you format a card with a capacity over 128 GB with
this camera and then insert it into another camera, an error may be
displayed and it may not be possible to use the card.
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