Formatted SD Card With Disk Utility Still has Folders on It (OS Catalina)

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Level 1

16 points

Formatted SD Card With Disk Utility Still has Folders on It (OS Catalina)

I got a new 256 GB V30 Sandisk Extreme SD card for shooting video. I formatted it in camera as I always do, but that caused errors. The camera said the card was full, then froze and I had to manually reset it by removing the battery. This happened repeatedly in both card slots, and I can't reformat in camera.

I tried reformatting on my up-to-date MBP using an external card reader and ExFAT format in Disk Utility, but that failed to work. It ran for hours and didn't complete.

Last ditch I tried reformatting the disk on an older IMac running Catalina, this "worked" in the sense it said it completed. But when I open the card in finder it still has the Panasonic DCIM file structure from my initial format in camera. Why is that still there if Disk Utility erased the SD card?

I can accept I got a bad card, but this is still weird. Is it just that because it's an older OS, Disk Utility is no longer functioning as it should?

iMac 27″, macOS 10.15

Posted on Dec 19, 2024 6:41 AM

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Answer 1

varjak paw

Level 10

179,650 points

Dec 19, 2024 8:27 AM in response to documental

While I can't say for certainty since I can't test the card myself, it does sound to me like a defective card given that it won't reformat in two devices and apparently fails to format correctly (which is why it still shows folders) in another. I'd recommend returning the card and getting a replacement and see how that behaves.

Regards.

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Answer 2

HWTech

Level 9

61,406 points

Dec 19, 2024 8:50 AM in response to documental

Does the SD card have a read-only mode switch?

If you are using an M-series laptop, did you grant the SD Card & adapter permission to attach to the laptop in the Privacy & Security System Settings? Maybe configure the "Allow Accessories to connect" to "while unlocked" to see if that makes a difference.

Within Disk Utility click "View" and select "Show All Devices" so that the physical drives appear on the left pane of Disk Utility. Select the physical SD Card item and erase it using the partition type & file system compatible with your camera. Erasing an existing volume from the factory generally results in problems, so erasing the whole physical drive usually correct any possible issues by also creating a new partition table.

Another option would be to write zeroes to the beginning of the SD Card, but that requires the use of the command line. Writing zeroes to the beginning of a drive will erase hidden items from the factory that can cause macOS problems.

Otherwise I agree with @varjak paw that it sounds like the SD Card is bad.

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Answer 3

tbirdvet

Level 6

14,711 points

Dec 20, 2024 1:51 PM in response to documental

In disk Utilities if the card shows a file structure be sure you select the top line before formatting so all sub directories are erased.

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