Canon 5D MkII won't format ExtremePro 90 MB/s CF cards

Have bought two new cards to use, camera is running latest firmware.  Camera gives an error that it can’t format the card, and won’t take any photos until the card is formatted.

Have read and formatted the cards on two computers using CF adapters, camera still won’t use or format the cards even after formatting on a computer to FAT or FAT32.

Very frustrating and would appreciate some help please :frowning:


in that case the card seem to be defective and needs to be replaced. you can replace it with the place of purchase or direclty with Sandisk under this link

Seems like two defective cards…bought from the US and the RMA from SanDisk isn’t accepted in Australia…we must be too far away :frowning:


in that case you can send them an email asking for a replacement.

you can contact them through here