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PowerShot SX740 HS Only Sees Memory Card as Locked


My Canon SX740 HS will not read a Sandisk Extreme Pro SDXC USH-1 300mg/sec. No matter where I set the lock switch, the camera sees it as locked. I reordered the card and got the same results. Any help?




2 cards with thew same issue?  Try this.  Remove the card.  Reset the camera's settings to default.  Power off the camera, ensure the card's protection switch is off.  Re-insert and re-test.  If it continues, the sensor in the card slot might be faulty or need service.  

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I have no problem using a smaller card and Canon says that this camera should handle the 128 gb. Thanks for responding.


What SIZE (Capacity) is your memory card?  Yes, though your camera is "compatible" with SDXC, there likely is a limit as to how big a card it will work with. 32GB is usually a sure thing. 64GB is less likely.. You're better off having multiple smaller cards than one huge one anyway, for safeguarding what you shoot.

It is a 128gb card. Canon says that the camera will handle that. So, I'm thinking it's the speed? I use a 64gb extreme Pro and 170 mb/sec without issue. Thanks for your response


You answered your own question. You can read a lot of threads on here about cameras that do not like SD cards larger than 32GB, maybe 64GB, despite what the manual says. It's not speed-related. They just don't like larger cards.

128GB is a very big card. You shouldn't be leaving so many photos on one card that you need more than 32GB. Even that is a lot. Having thousands of photos on one card is risking great loss if a card goes bad, is lost or damaged, etc. Rotate multiple cards for safety. Move files to your computer, external storage, etc. One card in the camera shouldn't be long-term storage.

Thanks. I always back up to a laptop and back the laptop up to two different extra hard drives. I'll return this card and order a smaller one.


Good luck returning the 128. Get MULTIPLE smaller cards.

Amazon Prime takes them back without much difficulty, but I do pay for that through the yearly fee.