Create a backup. Make sure that you have a current backup of your important files. Start up from macOS Recovery. Turn on your Mac, then immediately press and hold.
Mac How To Erase And Reinstall
Updated December 2, 2020: added information for new Macs with Apple processors.
- You can wipe your Mac computer — or, in other words, factory reset it — through the macOS Utilities menu. This is a good plan if your Mac is malfunctioning, or you're looking to sell it.
- Click the Erase button in the toolbar, then enter the requested details: Name: continue to use Macintosh HD as the name or enter a different name. Format: continue to use APFS or Mac OS Extended (Journalled), as recommended by Disk Utility. Click Erase Volume Group. If you can't see this button, click Erase instead.
All too often I’ve seen people buy a used Mac only to find that the seller did not properly erase the Mac first. Sellers sometimes just delete their documents, leaving poorly configured and obsolete apps lying around. Or worse yet a malicious security threat or connections to their old account. Here is how to properly erase a Macintosh, ensuring that:
- If you are selling or recycling your Mac, none of your personal information remains
- If you are buying a used Mac, none of the previous owner’s configuration will mess things up
Take note of what system version you are running, as some of these instructions will vary depending on the version. You can find that in the Apple menu > About This Mac.
Back up any data
These steps will completely and irrecoverably erase everything on your Mac. If you have anything on this Mac that you want to keep you’ll want to back it up. Photos, contacts, documents, application installers, etc. Many of these things are saved to iCloud but not necessarily. When we are done the only thing left will be a squeaky clean computer as good as from the factory.
Update your software (optional)
If the computer is going to be reused or sold, you probably want to upgrade the software to the latest supported OS if it isn’t already. It’s better to do an upgrade and then erase rather than an erase and then upgrade. If you’re planning to simply recycle the computer it doesn’t matter so you can skip this.
You can view my reference chart to see what version of macOS you can run, and where to get each version.
Log out of your accounts
This isn’t strictly necessary but it will remove one of your five allowed iTunes authorizations and will remove the computer from your iCloud account. In particular, you’ll want to:
- Deauthorize iTunes. Instructions are the same for the Music app in macOS Catalina. You only need to do it for Music or Apple TV, not both.
- Log out of iCloud (in the Apple menu > System Preferences > iCloud), if prompted you can delete the local data, since you have all of this in iCloud already.
- Log out of iMessage (open iMessage, click the iMessage menu, click the Accounts tab, click the iMessage account on the left column, and then click the button to sign out)
- Log out of FaceTime (similar to logging out of iMessage).
- Deactivate any third party software that has a limited number of authorizations. Most consumer-grade software doesn’t do this, but some expensive professional software does. Instructions for this will vary depending on the specific software.
Start up in macOS Recovery Mode
Be sure to remove all devices from your computer except for necessary items like the mouse and keyboard. You don’t want to accidentally erase an external hard drive.
For macOS 11 or higher with an Apple processor
- Turn your computer off
- Press and hold the power button until you see icons
- Click the Options icon then click Continue
For macOS 10.7 or higher with an Intel processor
- Turn your Mac off
- Press the power button to turn the Mac back on and immediately press and hold the Command + R keys on your keyboard
- When you see the Apple logo or globe you can release the keys
- Follow any prompts such as entering your WiFi password or choosing your language
Shortcut: If you are running macOS 10.13 High Sierra or later and you want to install the latest OS your computer supports rather than the currently installed OS, use Command + Option + R instead. You can release the keys when you see the globe, then choose your WiFi network when prompted.
For Mac OS X 10.6 and lower
You’ll need to boot using a Mac OS X disc. If you don’t have your disc you may need to upgrade the system software to a newer version first and then try again. Or you’ll need to enter Target Disk Mode and connect it to another Mac to erase with Disk Utility. Aurora hdr 2018 1 1 2 – advanced hdr software.
- With the computer powered on, insert your Mac OS X install disc or the recovery disc that came with your Mac
- Turn off your Mac
- Press the power button to turn the Mac back on and immediately press and hold the Option key on your keyboard
- Release the Option key when you see the boot selector
- Use your arrow keys on your keyboard or your mouse to select the install disc (it could take up to a minute to appear)
- click the arrow below the install disc or press Return on your keyboard to activate it
Erase your disk
For Macs with an Apple Processor
- Use the WiFi icon in the upper right corner of your screen to connect to WiFi if you are not already
- Click the “Utility” menu on the top of the screen and choose “Terminal”
- In the terminal window type resetpassword and then press return
- Click on the new window that pops up
- Click the Recovery Assistant menu
- Click “Erase Mac…” and follow the prompts to erase your Mac
For Macs with an Intel Processor
- Once in Recovery Mode, click the Disk Utility from the menu and then click “Continue”
- If running macOS 10.15 Catalina or 11 Big Sur you will see two similarly named drives on the left column, one with “Data” on the end. Click the Data drive to highlight it, then click the Minus Volume button above to remove the volume. Choose “Delete” (not Delete Volume Group). If you aren’t running Catalina or if you only see one internal drive skip this step.
- Click to highlight your hard drive name on the left column, Macintosh HD by default. If you are running macOS 10.12 or lower it will be indented slightly behind the model name of the hard drive.
- Click the Erase button. Depending on your OS version this will either be on the top button bar or on a tab to the right.
- If you want to destroy sensitive data, click the “Security Options” button and choose the level you want to run. Each pass takes about two hours depending on the speed of your drive. A single pass is good enough for most people. But consider more if you have any highly sensitive data. If you have an SSD or Fusion Drive you may not have this button because a standard erase is far more destructive.
- If the Format is listed as APFS, leave it as is. Otherwise make sure it says “MacOS Extended (Journaled)”.
- Click Erase and wait for it to complete. Erasing an SSD or an insecure erase takes just a few seconds. A secure hard drive erase can take hours. If it fails pretty much immediately just try again. Sometimes it takes a couple of tries. If it runs for a long time and then fails, you may have a bad hard drive.
- Click OK after it has finished.
- Close Disk Utility with the red dot button.
- Press Command-Q to shut down if you are just disposing of the computer, otherwise continue on to install the OS.
Install the OS (Optional)
If you are only recycling the computer and don’t need to prepare it for another user you can skip this step and shut down your computer by pressing Command-Q.
- Make sure you are connected to your WiFi network by clicking the WiFi icon in the upper right corner of your screen.
- Click the button to reinstall the OS and follow the prompts.
- After the OS is installed you can either go through the account creation process or, if you are selling the computer to someone else, press Command-Q to quit and shut down. The next time the Mac is turned on the new user will be greeted with the same welcome screen.
Requirements
- Fast internet connection: this will download the OS from the internet. It usually takes 30 to 60 minutes on a cable or fiber connection, or it could take 6 to 12 hours on a DSL connection. The download is about 6 to 8 GB.
- For macOS 10.11 or earlier, the currently installed OS must already be in your Mac App Store account. Check this in the Apple menu > App Store > Purchased. If the currently installed OS is not on your purchase list you must upgrade to at least macOS 10.12 and then do the full erase, or solicit the account of someone who does have the currently installed version in their account.
- Compatible network connection: Most home and small business routers since about 2005 should have the appropriate configuration by default. If you are unsure click the WiFi icon in the top right corner of your screen while holding the “Option” key. In light grey lettering you will see your current security type. Or just try it and see if it works.
You must be on either: Mac matte lipstick in mehr.
- wired ethernet connection,
- WiFi connection without a password, or
- WiFi connection with WPA-Personal or WPA2-Personal encryption.
You cannot install via:
- captive WiFi connection (one where you get a popup on connecting such as at a coffee shop or library),
- WiFi with WEP encryption
- WiFi with WPA-Enterprise encryption
- WiFi with certificate-based encryption, or
- a connection that requires a proxy to be configured.
Further help
If you are an existing customer who needs help with this or if you have other questions, or if you are in San Francisco and interested in becoming a client I invite you to book an appointment with me. Otherwise, you may wish to contact Apple Support or to find a local Apple consultant.
Photo by Kim Gorga on Unsplash
Boot Camp is a great tool for running Windows on an Intel-based Mac. However, a Boot Camp partition can take up a great deal of space on your Mac. So if you’ve stopped using it, you may want to delete it to save some space. In this article, we’ll show you how to remove a Boot Camp partition from your Mac.
What is Boot Camp?
Boot Camp has its origins in the transition from PowerPC to Intel Macs. One of the benefits of moving to Intel’s architecture was that it was much easier for Macs to run Windows. There was no longer any need for emulation software. Apple took advantage of this by building a tool, now known as Boot Camp, into macOS that allows you to partition your boot drive and install Windows directly onto one partition. You can then boot directly into Windows on your Mac using Boot Camp.
There are a couple of downsides to using Boot Camp. One is that Windows and its associated files and applications take up quite a bit of space on your Mac. The other is that you need to reboot your Mac every time you switch between Mac and Windows.
Boot Camp Assistant is the tool that’s used to create and manage partitions. You can download a Windows ISO from within Boot Camp Assistant and install it on the partition. You will need a license code for the version of Windows you want to install to use it.
If you need to uninstall Mac apps, don’t just drag them to the Trash. This won’t get rid of all the files the app places on your startup disk. Instead, you should use the app’s own uninstaller or a dedicated all-round uninstaller like CleanMyMac X, which can completely remove multiple apps with a few clicks.
How to delete a Boot Camp partition
Removing a Boot Camp partition is very straightforward: you can use the same tool, Boot Camp Assistant, as you used to create it in the first place. First, however, you should back up the Windows partition if you have any files or other data that you still need. You can do that manually from within Windows, by dragging files onto an external drive, by using a Windows backup tool, or from the macOS partition by using software that’s designed to clone a Boot Camp partition.
![Mac how to erase and reinstall Mac how to erase and reinstall](https://www.zollotech.com/wp-content/uploads/2018/07/erase-and-reset-mac-1280x640.png)
You should also back up your Mac using Time Machine or another backup tool before you start.
- Navigate to Applications > Utilities and launch Boot Camp Assistant.
- Click Continue.
- Press Restore.
- Type in your admin username and password and press OK.
Boot Camp Assistant will now begin erasing the Boot Camp partition and restoring your boot disk as a single partition. Once it has finished, your Mac will return to its pre-Bootcamp state.
How Erase Mac Hard Drive
Does Boot Camp run on M1-based Macs?
In November 2020, Apple launched the first three Macs to feature its own system architecture, M1, in place of Intel CPUs and other components. It seems clear from early testing that these Macs are much faster and more powerful than their Intel predecessors.
However, one of the casualties of the transition to Apple silicon is Boot Camp. It requires Intel architecture to work and so won’t run on M1 Macs. And with all Macs eventually migrating to Apple silicon, Boot Camp will be consigned to history. That doesn’t mean you won’t be able to run Windows on future Macs, though. Virtualization tools (see below) don’t rely on Intel chips, and their developers are already updating their tools to work in Big Sur on M1 Macs.
Alternatives to Boot Camp
If you chose to remove Boot Camp because you didn’t like having to reboot your Mac every time you want to switch to Windows, there are other options. There are several virtualization tools that allow you to install Windows inside an app and then launch Windows as an app, or even launch Windows apps without booting Windows itself. If you choose to boot Windows, you can run it in a window or in full-screen.
In short, if you want a fully-featured virtualization tool that’s easy to set up and use and has lots of support, Parallels Desktop and VMware Fusion are good choices. If you only need to occasionally run Windows apps and don’t need lots of support, Virtual Box or Wine will do the job.
Whichever Windows virtualization tool you choose, you probably need to clear some space on your Mac and tune it up, so it runs smoothly. Here again, CleanMyMac X can help. It can remove junk files and optimize your Mac in just a few minutes.
1. Download, install, and launch CleanMyMac X.
2. Choose Smart Scan and press Scan.
3. When the scan is finished, press Run to clean up your Mac.
The final alternative to creating a Boot Camp partition on your startup disk is to install Windows on an external disk and boot from that, just as you would boot from a Boot Camp partition. Set up is much longer and more complicated than it is when you partition your startup disk. And it requires additional software. But once it’s done, you’ll be able to boot your Mac into Windows without losing any space on your startup disk.
As you can see, it’s easy to uninstall a Boot Camp partition on your Mac using Boot Camp Assistant. If you want to uninstall other apps or reclaim space on your disk, however, it’s a good idea to use a specialist uninstaller like CleanMyMac X.