To use any of these key combinations, press and hold the keys immediately after pressing the power button to turn on your Mac, or after your Mac begins to restart. Keep holding until the described behavior occurs.

Set the format to APFS (macOS High Serria and Mojave) or Mac OS Extended (journaled) for OS X 10.12 and below. After that, click the Erase button to start the partition process. Step 6: The next thing is to merge the EFI folders from Windows EFI boot drive and the USB installer, and for this, you can use an EFI mounter like Clover Configurator. This article will help you create a Mac OS X or macOS recovery USB drive to use in case of disaster or no boot from internal hard drive. Every Mac running OS X Lion and later has a small (650MB) hidden recovery partition called Recovery HD located on your Mac’s internal hard drive which is reserved for common utilities such as Time Machine Backup,Terminal utility, Disk Utility, Hardware.

Command (⌘)-R: Start up from the built-in macOS Recovery system. Or use Option-Command-R or Shift-Option-Command-R to start up from macOS Recovery over the Internet. macOS Recovery installs different versions of macOS, depending on the key combination you use while starting up. If your Mac is using a firmware password, you're prompted to enter the password.
Option (⌥) or Alt: Start up to Startup Manager, which allows you to choose other available startup disks or volumes. If your Mac is using a firmware password, you're prompted to enter the password.
Option-Command-P-R:Reset NVRAM or PRAM. If your Mac is using a firmware password, it ignores this key combination or starts up from macOS Recovery.
Shift (⇧): Start up in safe mode. Disabled when using a firmware password.
D: Start up to the Apple Diagnostics utility. Or use Option-Dto start up to this utility over the Internet. Disabled when using a firmware password.
N: Start up from a NetBoot server, if your Mac supports network startup volumes. To use the default boot image on the server, hold down Option-N instead. Disabled when using a firmware password.
Command-S: Start up in single-user mode. Disabled in macOS Mojave or later, or when using a firmware password.
T: Start up in target disk mode. Disabled when using a firmware password.
Command-V: Start up in verbose mode. Disabled when using a firmware password.
Eject (⏏) or F12 or mouse button or trackpad button: Eject removable media, such as an optical disc. Disabled when using a firmware password.

If a key combination doesn't work

If a key combination doesn't work at startup, one of these these solutions might help:

Be sure to press and hold all keys in the combination together, not one at a time.
Shut down your Mac. Then press the power button to turn on your Mac. Then press and hold the keys as your Mac starts up.
Wait a few seconds before pressing the keys, to give your Mac more time to recognize the keyboard as it starts up. Some keyboards have a light that flashes briefly at startup, indicating that the keyboard is recognized and ready for use.
If you're using a wireless keyboard, plug it into your Mac, if possible. Or use your built-in keyboard or a wired keyboard. If you're using a keyboard made for a PC, such as a keyboard with a Windows logo, try a keyboard made for Mac.
If you're using Boot Camp to start up from Microsoft Windows, set Startup Disk preferences to start up from macOS instead. Then shut down or restart and try again.

Remember that some key combinations are disabled when your Mac is using a firmware password.

Learn more

Learn what to do if your Mac doesn't turn on.
Learn about Mac keyboard shortcuts that you can use after your Mac has started up.

I had a guy bring me in an old Mac Book Pro that had a corrupted hard drive. I saved his Data but then realized his computer was so old that I was going to have trouble getting a copy of OSX installed. His computer was no longer supported on current OSX releases. To make things worse his DVD drive wouldn't read a install disk. So this post is the result of me finding a way to resurrect an old Mac Book Pro. I hope it will help someone else in a similar situation.

Note:

Before starting this tutorial, ensure that you have a USB drive with at least 8GB of storage as well as a Leopard, or Snow Leopard retail DVD or disk image. Grey DVDs that were included with a Mac at the time of purchase cannot be used to make USB boot drives as they do not include drivers for Macs other than the computer it was shipped with. In this tutorial I will be creating a Snow Leopard USB install disk. The steps are the same to create one for Leopard.

Creating a Snow Leopard USB Boot Drive Using Disk Utility

Start by launching Disk Utility on the Mac. To do this, you can either search for the application in Spotlight or find it in the Applications folder. Locate the USB drive on the left-hand side of the window and click on its name, not its partition.

Boot Mac In Usb

Format the USB drive

Click the Partition tab
Under the Partition Layout header click on the 1 Partition option in the drop-down menu
Click the Format drop-down menu and select Mac OS Extended (Journaled).

Bear in mind that this will erase all data from the USB drive, so backup any important files before proceeding.

Make windows read mac os journaled driv. If you want to High Sierra or later versions, just use the Convert to APFS feature on Disk Utility. In this case, you can use other tools instead of Disk Utility.In this article, I will guide you to create a Mac OS Extended (Journaled) partition with GParted. Disk Utility will report. This error occurs because the partitions created do not comply with Apple’s.

To format the USB drive drive, click the Apply button in the lower right-hand corner of the Disk Utility window.

Snow Leopard, DVD or Disk Image

Locate a Snow Leopard disk image or DVD on the Mac
If you're using a disk image, mount it to the desktop
In the Disk Utility window, click the Restore tab in the USB drive's menu

In the center of the window you'll see two boxes: one labeled Source and another Destination.

Drag-and-drop the USB drive's partition into the Destination box
Drag-and-drop the Mac OS X Install Drive disk into the Source box
At the bottom right-hand corner of the screen and click the Restore button

Disk Utility will restore the OS X Install DVD or disk image to the USB drive; this process may take anywhere from 20 minutes to an hour depending on how quick the Mac is.

Using The Snow Leopard USB Drive

Now that you've created a Snow Leopard USB drive, let's use it to install OS X Snow Leopard as well as access Terminal, Disk Utility, and other OS X utilities.

Power down the Mac and reboot while holding the Option key
Select the OS X Install DVD from the boot menu using the arrow keys on the Mac's keyboard
Select the language you'd like to use when prompted

Installing OS X Snow Leopard

To install OS X Snow Leopard from the USB drive, you'll need to reformat the Mac's hard drive. To do this, look towards the top of the screen and click on Utilities from the top menu and then click Disk Utility from the drop-down menu. Uninstall cylance mac.

Formatting The Mac's Hard Drive

Click on the Mac's hard drive name
Click the Erase tab
Select Mac OS Extended (Journaled) from the Format drop-down menu
Name the drive whatever you'd like

Boot Mac Os X Pc Usb Drivers

Please note that all data on the Mac's hard drive will be erased, so backup all important files before proceeding.

Press the Erase button to format the Mac's hard drive

Starting The Snow Leopard Installer

Quit Disk Utility by pressing Command-Q