Re-Image Intel Mac Laptop & Desktop (COFC Image, Loaner, or Personal)

How do I:

How do I wipe and reinstall macOS on Intel based Macs?


Field Technicians


Re-imaging computers is a common procedure. It is required to be done with newly purchased mac computers. It is also commonly used for resolving some computer errors.


1. Confirm Machine is Enrolled In Jamf (Skip Step On Personal Machines)

This step must be preformed prior to starting the Re-Image, if this step is missed you may need to wipe the machine and start over.
Confirm that the Mac is enrolled in the MacPreStage DEP configuration:
  1. Navigate in a browser (on another computer) to JAMF Pro Dashboard
  2. Log in with Cougars credentials
  3. Select Computers --> PreStage Enrollments --> MacPreStage
  4. Select Edit, then select Scope
  5. Enter the Mac's serial number in the Filter Results search box
  6. If the checkbox to the left is selected, and the PreStage Enrollment Status column states anything other than "Unassigned", continue to the next section
  7. If the checkbox to the left is not selected, check the box, then select Save
  8. Double check the checkbox to confirm it is now selected

2. Wipe & Reinstall from macOS Recovery/Flash Drive

There is two ways to install MacOS onto the machine. The quickest way is via a flash drive containing MacOS (Only available on machines that do not have a Apple T2 Security Chip). The second way is to install via macOS Recovery. macOS Recovery is performed over the Internet. If a wireless network is available, you can choose it from the Wi-Fi  menu in the menu bar. It is recommend that during this step you are using a wired Internet connection. Without the wired Internet connection Jamf may not see the machine upon reinstall.


Start up from macOS Recovery (Skip Step if Imaging with Flash Drive)

To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following combinations on your keyboard. Release the keys when you see an Apple logo, spinning globe, or other startup screen.

Command (⌘)-R

Reinstall the latest macOS that was installed on your Mac (Not-recommended, may downgrade user but works for older machines).


Upgrade to the latest macOS that is compatible with your Mac. (recommended)


Reinstall the macOS that came with your Mac, or the closest version still available. (Not-Recommended, may downgrade user but works for older machines)


Start up from Flash Drive

To start up from a flash drive, turn on your Mac and immediately press and hold the following key on your keyboard. Release the keys when you see the startup manager. (image below)


Reinstalls the macOS that's located on the flash drive, locate the flash drive and press enter.

Startup Manager showing disks available for startup


Boots to macOS Utilities Menu

When you see the utilities window, you have started up from macOS Recovery/Flash Drive.


Big Sir or new MacOS Utilities

Downloading and installing macOS Big Sur via macOS Recovery's Terminal |  Der Flounder

Catalina or older MacOS Utilities


Erase (format) your disk

Select Disk Utility from the Utilities window, then click continue. please format the drive and rename it as "Macintosh HD". It is recommended during this process that you use the format Mac OS Extended (Journaled). The machine will automatically upgrade the format to APFS (Apple File System) if supported on the hardware. If your unsure how to format a drive learn more about how to erase a mac drive.


Install macOS

When you're ready to reinstall macOS close Disk Utility, choose Reinstall macOS from the Utilities window. Then click Continue and follow the onscreen instructions. You will be asked to choose a disk on which to install.

install macOS Big Sur

Please allow installation to complete without putting your Mac to sleep or closing its lid. During installation, your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.

Once the installation is done the Mac restarts to a setup assistant

macOS Recovery/flash drive exceptions

The version of macOS offered by macOS Recovery might differ in certain circumstances:

  • If macOS Sierra 10.12.4 or later has never been installed on this Mac, Option-Command-R installs the macOS that came with your Mac, or the closest version still available. And Shift-Option-Command-R isn't available.
  • If you erased your entire disk instead of just the startup volume on that disk, macOS Recovery might offer only the macOS that came with your Mac, or the closest version still available. You can upgrade to a later version afterward.
  • If your Mac has the Apple T2 Security Chip and you never installed a macOS update, Option-Command-R installs the latest macOS that was installed on your Mac.
  • If you just had your Mac logic board replaced during a repair, macOS Recovery might offer only the latest macOS that is compatible with your Mac.


3. Setup macOS and Device Enrollment Program (DEP)

The computer will boot to the Mac setup assistant, before proceeding confirm Internet connection, follow the onscreen instructions until you get to the Remote Management screen. If its a personal machine the machine is ready for the end-user to setup. Please use your Cougar credentials for the username/password. Make sure during this step your connected to the Internet. (It may take multiple times to sign in). If missing remote management, this article may help.

Once remote management finishes it will load the Mac setup assistant again then continue to follow the onscreen instructions.

Department Setup

Once the Mac setup assistant is complete you should be presented with the Mac login screen. Please use the "acts" account for the login information and not your personal account. If your unsure of this account information please speak with your management team.

Once logged into the computer wait a few minutes until you are prompted with the DEP Configuration and follow the onscreen instructions. There will be 3 onscreen instructions. It is recommended that you use the correct department that this machine is located in. If this is for a CofC IT Service Desk loaner, please use CofC DEP: Faculty and Staff, IT as the set Department name, and ActsTech as the AD group. Once the instructions are filled out it will auto-start the installation of our COFC campus software. This step can take up to 45 minutes. When the installation completes it will restart the machine and boot to the Mac login screen.

Please log into the acts account and confirm the computer has the campus software and Self Service installed.




Article ID: 94787
Thu 12/19/19 4:43 PM
Fri 10/28/22 3:39 PM

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