I am on the road headed to a job and started up my 5D to take a few stills in a cool campground this morning and yikes a problem. The camera says "can not format the card change cards. This is the same card I just shot on two days prior and downloaded to my computer the same day. I have used this card for two months.

OK so I tried 4 more cards that are all have been used and say the same thing. The CF cards are Sandisk 32GB Extreme III and Extreme Pro.

Has anyone else had this problem? If so do you know a fix or what I can try for a fix? We were hoping to use this camera on a 4 day shoot starting Sunday. Of course I have 5 other cameras with me but we need to grab some nice stills of the job.

Thanks if anyone can help out. I am driving all day today and most of tomorrow. Will check email often but can't respond till I stop later today.

If ALL your cards are doing this then it sounds like a camera problem.

Do the cards work in your other cameras?

Thanks Dave,

I guess I was not clear enough, yes it is the camera. The other cameras are video cameras since I don't use the 5D for video only stills.

Hate to say it but this same thing happened to me - it was a bent pin in the camera, take a look inside and see if any of the pins are flattened. I had no luck in my attempts to straighten the bent pin and had to send it in to Canon, ended up being a $200 repair + shipping costs.

Thanks Evan I bet that is it. I looked and could not see a bent pin but I was in a hurry. More time tomorrow so I will check it out.

Well I could not get the camera to work so I sent it off to Canon Service after filling out their form. Camera arrived Monday and two days later today they said it was fixed and shipped back no charge. FedEx says it arrives today. I did send the warranty info and original receipt.

I still don't know what the problem was and will try and find out today through Canon. One thing I can say is Canon is on top of it when it comes to service. This is the second time I have dealt with their service center and they are top notch.