MacBook Pro external drive: this computer is missing a firmware partition

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Level 1

8 points

MacBook Pro external drive: this computer is missing a firmware partition

Trying to upgrade from Sierra 10.12.8 to Catalina. Can't choose external hard drive because it says "this computer is missing a firmware partition. My hard drive died and I bought an external one to use as my startup disk. Worked great and reinstalled Yosemite (it's an old MacBook Pro!). From there, I upgraded to Sierra. I'm now trying to upgrade to Catalina so that I can use my Adobe Creative Suite apps. But when I choose my external hard drive it gives me the message "You man not install to this volume because the computer is missing a firmware partition." I have no idea what to do now.

[Re-Titled by Moderator]

MacBook Pro 13″, macOS 10.12

Posted on Nov 19, 2024 10:57 AM

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Answer 1

TheLittles

Level 10

195,705 points

Nov 19, 2024 8:21 PM in response to stephk78

stephk78 Said:

"MacBook Pro external drive: this computer is missing a firmware partition"

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Transfer this Data:

Are you trying to backup your Mac here? Or are you looking to transfer data? You can transfer this using Migration Assistant. So you that, you need to create a Time Machine Backup. And to do that, you'd need to format the hard drive accordingly. So, for Sierra, APFS is what format to use. Perform this formatting in Disk Utility.

Reinstall the macOS:

Nothing would be lost. It's just that misplaced items would be placed back to where they should be and corrupt system files would be replaced by clean files. Go Here: Reinstall macOS - Apple Support. Use the third bulleted method: [command + r]. Important: Prior to installing an update or performing a reinstallation, to prevent data loss, be sure to Back up your Mac with Time Machine.

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Answer 2

TheLittles

Level 10

195,705 points

Nov 20, 2024 10:18 AM in response to stephk78

stephk78 Said:

"MacBook Pro external drive: I have nothing on my computer I need to backup. Here are the steps I followed after my computer had the blinking folder with a question mark:[…]”

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Great work!

If Stuck in a Boot Loop while Installing:

Perform the three steps:

1. Repair the Disk in Disk Utility:

While in Disk Utility, make sure the drive is mounted. Also, click First Aid and see if the drive is damaged in anyway.

2. Use Ethernet:

Rather than relying on WiiFi, use Ethernet, instead. Ethernet gives you a more reliable

connection. You’d hook you computer up to the wall or directly into the router or modem. If you have no Ethernet, then this is the adapter to use: Belkin USB-C to 2.5Gb Ethernet Adapter - Apple

3. Install with a USB Bootable Installer:

With a USB Bootable Installer, you can install this without having to go through the Internet. You’ll need a Mac to create one. So, if you have no other Mac, and ask a friend if you may user his/her Mac to create one. Go Here: Create a Bootable Installer for macOS - Apple Support

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Answer 3

stephk78 Author

Level 1

8 points

Nov 20, 2024 6:48 AM in response to TheLittles

I have nothing on my computer I need to backup. Here are the steps I followed after my computer had the blinking folder with a question mark:

I reinstalled Yosemite using Internet Recovery and attached a new external hard drive to use as my startup disk.
I installed Sierra, which was a higher OS system that didn't require me to use my apple id which wasn't working for some reason.
Trying to upgrade Sierra to Catalina. It said I couldn't choose my external hard drive because it was missing a partition.
I opened disk utility and erased the external hard drive.
I was able to start installing Catalina but now it just loads, restarts, loads, restarts.....

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