Do you need to reinstall macOS? Maybe your Mac is playing up, and you want to see whether installing a clean copy of macOS fixes the issue? Or perhaps you’re about to stick your Mac up on eBay, and need to restore its factory settings before sending your Mac along to its new owner?
Whatever your motivation, there’s several ways that you can install a clean copy of macOS, including a way to reinstall macOS without a recovery partition.
Before we begin
Before reinstalling the operating system, make sure you’ve backed up any files or data that you want to hang onto. Reinstalling macOS shouldn’t delete your data, but it’s always best to be on the safe side!
You may even want to consider actively wiping your data before reinstalling macOS, especially if you plan to sell your Mac, or donate it to a lucky friend or relative.
In this article, I’ll show you how to reinstall macOS via Recovery Mode, and via Internet Recovery – just in case your Mac is missing a recovery partition! However, regardless of whether you reinstall via Recovery or Internet Recovery, at some point you’ll have access to the macOS Utilities menu, which contains a ‘Disk Utility’ option that you can use to wipe your hard drive.
If you do decide to wipe the slate clean, then as soon as you encounter the macOS Utilities window, make sure you:
- Select ‘Disk Utility.’
- Select the volume that you want to erase.
- Click ‘Erase.’
- Disk Utility will now wipe your hard drive. Once the process is complete, select ‘Quit Disk Utility,’ to return to the main macOS Utilities window.
Installing a fresh copy of macOS via Recovery Mode
For the majority of Mac users, reinstalling macOS means booting into Recovery Mode:
- Restart your Mac while holding down the ‘Command+R’ buttons.
- Release these buttons as soon as you see the Apple logo. Your Mac should now boot into Recovery Mode.
- Select ‘Reinstall macOS,’ and then click ‘Continue.’
- If prompted, enter your Apple ID.
Your Mac will now reinstall macOS. One the installation is complete, the setup wizard will open and you’ll be able to configure your “new” Mac. If you plan to sell your MacBook or pass it along to someone else, then you should quit this wizard so that the new owner can enter their own details.
Is your Mac refusing to boot into Recovery?
Sometimes, it may not be possible to boot into Recovery Mode, for example maybe your recovery partition is corrupt, the startup volume has been erased, or you’re reinstalling macOS due to a complete hard drive failure.
If you’ve tried the ‘Command+R’ shortcut and your Mac is either starting up as normal, or it’s displaying a blank screen, then you may be missing a recovery partition, which is required for booting into Recovery Mode.
If you want some additional confirmation that Recovery Mode really is missing in action, then you can view a list of all your Mac’s mounted drives and partitions, using the Terminal:
- Open a new ‘Finder’ window.
- Navigate to ‘Applications > Utilities,’ and launch the Terminal app.
- Type the following into the Terminal: diskutil list.
- Press the ‘Enter’ key on your keyboard.
- The Terminal will now display a list of all your drives and partitions. If this list doesn’t contain either Apple_Boot Recovery HD or APFS Volume Recovery, then your Mac doesn’t have a recovery partition.
Occasionally, it may be possible to restore a missing recovery partition, by resetting your Parameter RAM (PRAM). To reset the PRAM, restart your Mac while holding down the ‘Command+Option+P+R’ keys until you hear the startup chime for a second time. Once your Mac has booted, try re-running the ‘diskutil list’ Terminal command, to see whether this has resolved the issue.
Installing macOS via Internet Recovery
Even if you can’t repair your Mac’s recovery partition, don’t panic! As long as you have an active Internet connection, you can reinstall macOS via Internet Recovery instead.
To use Internet Recovery, you’ll need a network with WPA (Wireless Protected Access), WPA2, or WEP (Wired Equivalent Privacy) security. Most home or office networks should be protected with one of these security standards, but if you want to double-check, then:
- Select the ‘Apple’ logo from your Mac’s menu bar.
- Navigate to ‘System preferences… > Network.’
- In the left-hand menu, select the network that you’re currently using.
- Click the ‘Advanced…’ button.
- Make sure the ‘Wi-Fi’ tab is selected.
- Find your network in the ‘Preferred networks’ list. The network’s security protocol should be listed next to it, in the ‘Security’ column.
Once you’re confident that you’re on a secure network, you’re ready to boot into Internet Recovery:
- Restart your Mac while holding down the ‘Option+Command+R’ keys.
- Release these keys as soon as you see the Apple logo.
- Once your Mac boots, you should see a spinning globe and the message ‘Starting Internet Recovery.’ Eventually, this will be replaced by a progress bar and, finally, the standard macOS Utilities window.
- Select ‘Reinstall macOS,’ at which point Internet Recovery will download and install a fresh copy of macOS.
Before you go
After spending over 20 years working with Macs, both old and new, theres a tool I think would be useful to every Mac owner who is experiencing performance issues.
CleanMyMac is highest rated all-round cleaning app for the Mac, it can quickly diagnose and solve a whole plethora of common (but sometimes tedious to fix) issues at the click of a button. It also just happens to resolve many of the issues covered in the speed up section of this site, so Download CleanMyMac to get your Mac back up to speed today.