Questions tagged [efi]
Extensible Firmware Interface is a specification that defines a software interface between an operating system and platform firmware
347 questions
0 votes
0 answers
43 views
HELP! External HD not working... Corrupted EFI Name, need help rebuilding EFI?
kind of in a doozy here. So, I have a 8TB External HD that I have always mounted to my iMac that is running the newest version of Sequoia via OCLP. I'm not sure exactly what happened to the drive, but ...
2 votes
2 answers
103 views
How to ascertain the bitness of the EFI on macOS? [duplicate]
If I want to install another OS (say, a Linux-based one) on old hardware, with a 64-bit CPU, that originally came with macOS, I need to know what word size the EFI is, in order to know whether to add ...
2 votes
1 answer
885 views
How to make MacBook EFI boot order permanent?
I have an old MacBook Air 2015. I recently installed Linux Ubuntu 2024 on it on a new ext4 partition. I can dual boot between macOS 12 and Ubuntu whenever I want by holding option key on startup. ...
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1 vote
0 answers
80 views
Make a bootable Mac USB (NOT AN INSTALLER) on a Late 2020 M1 Mac
I am wondering if you can make an USB bootable without using a Bootable MacOS Monterey, Ventura, etc. I am asking you guys, if I have to add some special EFI partition with files in the USB or if I ...
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3 votes
1 answer
172 views
How to fix script which requires EFI System Partition (ESP) to be disk0s1 in macOS?
I see a post which is 12 years old: How to fix broken EFI partition? System: Macbook Pro 2019 with Intel & T2, upgraded to Sonoma. Objective: Dual boot with T2Linux Fedora using https://t2linux....
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2 votes
0 answers
132 views
How to completely remove MacOS (Ventura) from Macbook Pro 2019 with T2, and install Linux? [closed]
System: Macbook Pro 2019, Intel, T2, 16 GB RAM, No USB port (Using VIVA USB hub), Ventura 13.6.5 Issues: (1) Hash Volume Mismatch (2) Not re-installing MacOS (3) Bootable USB Drive is NOT showing up ...
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1 vote
0 answers
91 views
Change EFI label for external volume
I am booting a retrogaming system (Recalbox, linux-based) on my Macbook Pro 2009 (Intel, El Capitan) from an SD card (FAT format). The SD card is currently displayed as "EFI boot" upon boot ...
- 11
1 vote
1 answer
508 views
Mac OS X EFI and installing rEFInd on SD card with Linux OS
I have a MacBook Pro (2013) running Sierra on the internal SSD. I’ve installed Debian12 onto an SD card. Upon boot (by holding down the Alt key) it doesn’t show an option of EFI Boot. But having ...
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1 vote
0 answers
476 views
Is there any efibootmgr command-line equivalent in MacOS to see bootable targets?
I found this text in a book (on linux) and i was wondering if there is an equivalent in MacOS. "To determine if your system uses a BIOS or UEFI, run efibootmgr. If you get a list of boot targets,...
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1 vote
1 answer
3k views
Macbook Pro x86_64 Triple-Boot: How can I fix EFI boot and Startup Manager
Summary I successfully created a triple-boot on my 2015 MBP with macOS (Big Sur), Ubuntu 22.0.1, and Windows 10. I can boot into any of the 3 successfully, however, the Startup Manager does not show ...
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0 votes
1 answer
450 views
Restore partitions table
Just tried to install Windows on an external SSD, but mistakenly deleted partitions on a Mac SSD from the Windows installer. I had 2 partitions: Macintosh HD (APFS) MacData (ExFat, ~108 GB) So I ...
0 votes
0 answers
154 views
Are there keyboardless options to enter macOS Recovery Mode? (possible broken by bad Windows EFI purge)
I acquired a 2009 iMac that had a Windows partition which was apparently erased during formatting to be sold. The computer now tries to boot, via EFI, the missing Windows partition as default. I can ...
- 1
6 votes
1 answer
1k views
Can a Mac "boot" from the internet if the recovery partition is absent/corrupted?
This is something that has never been clear to me, and I can't find a clear and definite answer by searching the web (rather contradictory information). Can a Mac "boot" from the internet (...
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1 vote
0 answers
1k views
M1 MacBook Pro EFI Lock system PIN unlock situation on Monterey OS update
My M1 MacBook suddenly rebooted and locked asking for 6 digit system pin. I think it happened during macOS Monterey update on a public WiFi. Apple store didn't help as they couldn't confirm the ...
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1 vote
1 answer
3k views
No BOOT folder found in EFI partition
Excuse me if this already have answers elsewhere. My problem is that I cannot find the BOOT folder in EFI partition, the only thing exists is the APPLE folder. This is quite strange as I see in almost ...
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