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Can't reformat a drive in Disk Utility: grayed out

Acquired a Mac Pro Trash can Mac, and trying to reformat / reinstall the system. Starts up with folder / question mark on it. Went into Recovery mode (command+R) upon startup. Went to Disk Utility: recognizes the drive (says it's ok) / but cannot reformat it. It is a 1T SSD. Previous owner wiped it, but removed the system software etc. When I try to reinstall Catalina on it, the drive to put it on is not recognized. Do I need to get a new drive?

Mac Pro

Posted on Feb 4, 2023 9:22 AM

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Posted on Feb 4, 2023 12:24 PM

First, in Disk Utility, had you done View > Show All Devices and were you operating on the very top level of the drive (it will be named something like Apple HDD xxxxxx Media or Apple SSD xxxx Media)


You may need to use Internet Recovery (Option-Command-R) to reformat the drive ... but if you also install that way there's a possibility that you may only be able to install Monterey or Ventura depending on the specific model of your Mac Pro. (You may end up needing to create a bootable installer for Catalina, and that would require another Mac in order to create the bootable installer.)


Here is Apple's documentation on macOS Recovery: Use macOS Recovery on an Intel-based Mac - Apple Support


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Question marked as Top-ranking reply

Feb 4, 2023 12:24 PM in response to DrummingDad

First, in Disk Utility, had you done View > Show All Devices and were you operating on the very top level of the drive (it will be named something like Apple HDD xxxxxx Media or Apple SSD xxxx Media)


You may need to use Internet Recovery (Option-Command-R) to reformat the drive ... but if you also install that way there's a possibility that you may only be able to install Monterey or Ventura depending on the specific model of your Mac Pro. (You may end up needing to create a bootable installer for Catalina, and that would require another Mac in order to create the bootable installer.)


Here is Apple's documentation on macOS Recovery: Use macOS Recovery on an Intel-based Mac - Apple Support


Can't reformat a drive in Disk Utility: grayed out

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