256GB SD card is read as 268GB and cannot mount?
Hi,
I have a Samsung EVOPlus 256GB microSDXC card that I bought new, and formatted (Apple HFS on MacBook Pro 13” 2015 with MacOS 10.14.2) and was able to use for a few days fine (although it seemed a touch slow).
Now my computer is unable to mount the card (“This disk is not readable'“), although it shows up in Disk Utility as a greyed out internal physical volume with a capacity of 268.44GB. I’ve tried First Aid, but it says there’s an “Invalid key length”.
The stuff (about 3GB worth) on here hasn’t been backed up anywhere else yet, so I really want to try and save it all.
Any advice or tips? I don’t even understand how the system suddenly decided the card gained an extra few gigs!?
Thanks for any help you can give,
H
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FYI - High Sierra & Mojave both auto format flash & SSD drives with APFS file system which is different on how HFS+ works. For compatibility I strongly recommend you reformat the flash to exFAT so it works with your phone or camera.
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