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how to erase and format efi partition?

Joined
Oct 8, 2014
Messages
87
Motherboard
Gigabyte GA-H97N-WiFi
CPU
i3-4360
Graphics
HD 4600
The EFI partition is valid. The mounting script doesn't work for whatever reason. Try this
Code:
$ diskutil mount disk0s1
$ diskutil rename disk0s1 EFI
macOS apparently ignore the name in the partition table and only considers filesystem label, neither of which are required by UEFI (and neither is the partition GUID for that matter)

'MBR: Protective' Normal GPT disks have an old style MBR partition table, alongside the GUID partition table that masks the entire disk as being taken up by a single MBR partition. Without this, legacy software that cannot understand GPT would see the disk as empty creating a potential for confusion and data loss, hence 'protective'.

Won't let me, do you think the lacking of a name is what's preventing me to mount it?

Code:
sudo diskutil mount disk0s1
Password:
Volume on disk0s1 failed to mount
If the volume is damaged, try the "readOnly" option
If the volume is an APFS Volume, try the "diskutil apfs unlockVolume" verb

sudo diskutil mountdisk disk0s1
Volume(s) mounted successfully

sudo diskutil rename disk0s1 EFI
Volume must be mounted

I suppose I could reinstall Mac OS again and restore my TimeMachine backup


UPDATE !!! Successs !!! I used gdisk and d to delete the entire partition, then create a new one with n, chose the sectors as it was before then type and name , rebooted and voila !!! There it is !!

Thank you so much for your help mate, you've saved me and now I know about gdisk for future mess ups hahahaha

Big Cheers !!!! :thumbup::clap::clap::clap::headbang:
 
Last edited:
Joined
Jul 24, 2015
Messages
2,280
Motherboard
MSI H81i
CPU
i5-4570
Graphics
RX 580
Won't let me, do you think the lacking of a name is what's preventing me to mount it?

Code:
sudo diskutil mount disk0s1
Password:
Volume on disk0s1 failed to mount
If the volume is damaged, try the "readOnly" option
If the volume is an APFS Volume, try the "diskutil apfs unlockVolume" verb

sudo diskutil mountdisk disk0s1
Volume(s) mounted successfully

sudo diskutil rename disk0s1 EFI
Volume must be mounted

I suppose I could reinstall Mac OS again and restore my TimeMachine backup


UPDATE !!! Successs !!! I used gdisk and d to delete the entire partition, then create a new one with n, chose the sectors as it was before then type and name , rebooted and voila !!! There it is !!

Thank you so much for your help mate, you've saved me and now I know about gdisk for future mess ups hahahaha

Big Cheers !!!! :thumbup::clap::clap::clap::headbang:
Glad you got it fixed.
 
Joined
Oct 8, 2014
Messages
87
Motherboard
Gigabyte GA-H97N-WiFi
CPU
i3-4360
Graphics
HD 4600
Glad you got it fixed.
Nevermind hahahahha , When I went to mount disk0s1 it mounted because my Data Drive had become disk0 .

Hackintosh is now Disk1 and still shows EFI as Type , But No Name and can't mount.

I did the whole thing again on now Disk1 and no difference.

I think I'll just re-install Mac OS whenever I get the time , now to keep booting from USB until I get it sorted :(

Thank anyway mate !
 
Joined
Jan 17, 2013
Messages
7
Motherboard
GA-Z270X-Ultra
CPU
I7 7700
Graphics
GeForce GTX 1070ti
Mac
  1. iMac
I was having the same error, but you have to format the disk in terminal and it will create the EFI partition
First
diskutil list ( to learn the number of the disk)
diskutil eraseDisk JHFS+ Transfer disk#
 
Joined
Mar 17, 2020
Messages
1
Motherboard
Undefined
CPU
Intel i7-6700HQ
Graphics
NVIDIA GeForce GTX 950M
No in my experience

terminal

sudo -s
type password
diskutil list

find efi disk #

ewfs_msdos -v EFI /dev/diskXsX

for example disk0s3 or disk1s3
Simple and useful, I love this answers.
Thanks a lot man.
 
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