my 7d is not reading all my cards

[Akdave]

My 7d does not recognize all of my compact flash cards not the CF adapter for SD. Any suggestions

[jrhoffman75]

CF adapters can be a problem. If it's reading real CF cards then the camera is working properly. 

[ebiggs1]

Buy only top quality cards from a good retailer.  But anybody can get a faulty card and they do go bad occasionally.

[ScottyP]

It recognizes none of them, or do some work?

[Akdave]

Some of the cards will work some not, I have tried them in my 20D and some of the cards that did not work in the 7d will work in the 20D, It all seem to happen at once had been uililizing a CF Adapter Big Gear with a 128 gb micro high speed worked great

[kvbarkley]

You might try to peak inside to see if any of the pins are bent.

[ebiggs1]

"CF Adapter Big Gear:"

What is this?  Any adapter is a bad idea.  Never use any adapter.  Use the cards as they come.

[jrhoffman75]

Bent pin(s) was my thought, but OP says some work and some don't.

[kvbarkley]

Can't hurt to look....

[jrhoffman75]

Agree.