3 hours ago One or more volume(s) failed to mount-But for the first time in days, the icon for my hard drive appeared on the desktop. It just says 'EFI' and none of the data are there. The disk utility shows WD My Passport with External Drive grayed out underneath it. Tried clicking mount. I also tried efi only to confirm the results. On the Z420 there are 3 efi settings, the efi/legacy settings in advanced storage drivers (efi is efi only) and the boot options which allow uefi to be disabled or the various uefi devices to be disabled/enabled (the efi partitions, windows boot loader is the HP default). The general idea should be the same, with EFI signifying your EFI boot partition. For instance, my EFI identifier is disk0s1, take note of your identifier, because you'll need it in a second. But first, we have to make a mount point to access the partition. To make the said mount point, run the following: sudo mkdir /Volumes/EFI. The EFI package was key to getting my Mac to see the USB drive on boot-up. Also, make sure to format the USB stick with Disk Utility with GUID Partition Map and MS-DOS (FAT), nrot exFAT and not.
According to WIkipedia, “On Apple–Intel architecture Macintosh computers, the EFI partition is initially blank and not used for booting. However, the EFI partition is used as a staging area for firmware updates.” When people look to create non-standard boot environments or attempt to build a hackintosh, the first step is often mounting and modifying the EFI boot partition. Before you read any further, take note: altering your EFI boot partition is not supported by Apple and The Mac Admin takes no responsibility if you render your computer(s) unbootable by mounting and modifying this partition.
To mount an EFI boot partition, follow these steps:
1. Discover the volume identifier for your EFI boot partition.
Run this command:
The output should look something like this:
In this case, the volume identifier of the EFI partition is disk0s1
2. Create a mount point.
A mount point is a directory where a non-booted volume is mounted. On Mac OS X, mount points are typically created in /Volumes. We can create a directory called efi within /Volumes by running the following command:
3. Mount the EFI partition at the efi mount point.
Run the command:
Efi Mounter For Mac Mojave
Mount Efi Windows 10 Hackintosh
That’s it. Your EFI volume will be mounted. Modify it at your own risk.