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Help with EFI Partition

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Help with EFI Partition

To upgrade my OC from 0.6.4 to 0.7.3, I created a USB with OC 0.7.3 and can successfully boot with it. When I went to copy the EFI folder to the EFI partition on the startup drive (originally OC 0.6.4), the EFI partition shows no files and there are only 64 bytes available. I tried showing invisibles just in case some random flag was set. Nothing. I tried copying the new EFI folder from my USB to the EFI partition on my startup drive. The Finder reports not enough disk space. I tried emptying the trash with the EFI mounted just in case somehow the files were moved. No change. Get Info shows 206.5 MB used. The EFI partition is Fat32.
Screen Shot 2021-10-21 at 3.02.33 PM.png
I'm not sure if this is related to Carbon Copy Cloner snapshots. I found that the snapshot function used about 1.4TB of my SSD disk space so I deleted the back up snapshots. The EFI partition was not mounted at the time, so I'm not certain that this is related.

Can I safely reformat the EFI partition to FAT32 without messing up the ability of the BIOS to see it? Is there another possible solution?

Any help with this is greatly appreciated.

Thanks.
 
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you shouldn't have an issue reformatting the partition. You can actually format an entire USB Drive as fat32, and label it EFI, and the bios will acknowledge it the same way. This is what I do for my rescue Bootloader in case I make changes and can't boot.
 

UtterDisbelief

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USB isn't my problem. I was hoping to reformat the EFI partition on my system drive so I could put the USB aside as an emergency backup. Any idea how to do that?

Yes you can reformat the FAT32 EFI partition on it's own and not affect the rest of the drive - because you are not changing the drive's Partition Map. If you do that by mistake then you lose everything.

However you have to use the Terminal version of Disk Utility, so be careful with your command. Use the Help function.

You will still be able to boot the system using your USB memory stick, then copy the new EFI into place.
 
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