It was working fine, then suddenly it won't read a CF card. I get a message saying Card not formatted. I've tried a new card. Reformatted the new and the old card.
The camera is not reformatting the old or the new.? A new card should format just fine in camera, the most likely issue is the old card finally died. But if a brand new card is not working either that is more concerning for sure. If a new car wont read, there may be damage to the pins in camera, you could factory reset the camera to make sure to remove any possible bug in the system, but you cant really reach, fix, or clean those card reader pins if the issue is the hardware.
A bent pin in the card socket is the most likely cause. This usually happens because a CF card has been used in a cheap card reader which has mis-aligned pins, this damages the CF card then the CF card ends up bending pins in the camera. The pins in the camera can sometimes be realigned if the damage isn't too great but this does take very careful manipulation othewise the pins can break off. I would advise that your card reader should be replaced with one of reputable make and the original CF card should be scrapped and not used in anything else.
Yup. I got a magnifying glass app, and it's a bent pin. The camera cost me nothing so I'll have a go at straightening it. Thanks.