USB not recognized after flash of iso

So I got a thumb drive large enough to hold a Linux iso image file today.

I plugged it into my old Macbook Pro and used Etcher to flash my verified iso file…apparently successfully.

But when the system then tried to access the file on the thumb drive, it said that it couldn’t.

So I used the Mac disk utility to erase the thumb drive. Then I checked in Finder to see if the system recognized it. It did show up with the name I had given it.

So I went through the Etcher flash process again…again apparently successfully. But once again the drive/file couldn’t be read. The thumb drive was now in the same condition/state as it was before I erased/reformated it. It was also no longer visible in Finder.

Am I missing something? I don’t think I missed any steps. Do I have a bad thumb drive? I don’t think so. It did let me copy a (different) file from my Mac to the thumb.

Any help/suggestions appreciated. At this point, I’m stumped.


Hello @Glsonn !

Welcome to the forum!
The initial flash you performed was successful. Since the bootable Linux USB thumb drive uses a different file format, it’s unreadable by macOS. You may be getting a message that it’s unreadable, but that’s to be expected.

The next step would be to reboot (with the USB thumb drive attached), hold the option key, and select the UEFI boot drive (which is your USB thumb drive).

Please remember to back up your files before you engage in any Linux installation!


Ah, that makes sense! Thanks for the info. Now back to trying it again.


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My pleasure, as always! :slight_smile:

Hm. After reboot, I go directly to MacOS with no option for Linux setup. I do get the message about the thumb drive not working again though.

Oh, never mind. I forgot the Option key. Doh! Will try again. (I’m usually quite tech savvy…really.)

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I am now an official Linux Mint user.


Bravo! Congratulations and welcome to your Digital Freedom!

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