5D question: Error 99

My 5D now gives me an error 99 when I release the shutter button. It starts the shutter release but does not completely finish the cycle/process.

I have tried the battery resolution as well as cleaning the lens contacts without any success. I don't think my camera has more than 2,000 actuations on it.

Has anyone come across the same situation?

What kind of CF card are you using?

Sandisk 8Gb. However the problem remains with other CF cards as well. The camera is going to the CFS.

Can you try a difference lens ? and try difference mode select : auto ,P , Tv ,Av ...etc .

Usually error 99 is when body can't recognize the attached lens. Old incompatible lens chips such a old Sigmas, dirty gold pins, attaching a TC on a manual lens via adapter, bent pins etc to be blamed. If your problem is resolved with a new lens you know where the problem is. If not you need to dig further in trouble shooting list.