It is possible that the EOS digital SLR cameras which have had their main PCB replaced during the specific timeframes listed above may not turn on normally when Eye-Fi brand cards are used, or if any brand of SD card is removed from the camera within a certain time after opening the card slot cover. If the camera is not turning on normally when using an Eye-Fi brand card, a temporary workaround is to use SD cards instead of the Eye-Fi card when capturing images. If the camera is not operating normally when the SD card is promptly removed after opening the card slot cover, a temporary workaround is to remove the battery pack, then re-insert the battery pack.
Target Eye-Fi cards
Eye-Fi cards with “X2” in the product name. For example: Connect X2, Mobile X2, Pro X2, etc.
We offer our sincerest apologies to customers who have been inconvenienced by this phenomenon. Canon strives to provide the highest quality products to our customers and we spare no effort in our quality management to make sure our customers use our products with confidence. We hope our efforts will earn your understanding.