Essential tasks when you have bought a second-hand Apple Mac

How to use recovery mode on the Apple Mac to erase the disk and reinstall macOS. Use it when you buy a second-hand Mac to start with a clean install

If you have just received or purchased a pre-loved Apple MacBook or iMac, what should you do? Before you begin using it there are some essential tasks to perform to ensure it runs perfectly.

Used Macs are available from a variety of sources and you might know a friend who is upgrading to the latest model. Some people have to have the latest MacBook and they could be getting rid of a model that it only a couple of years old and still has another five or more years of life left in it. You could offer to buy their old one off them.

eBay has lots of second-hand MacBooks for sale and at some very low prices too. It is worth spending some time checking them out if you are looking for a new computer and don’t want to pay a premium for the latest brand new model direct from Apple.

As always with eBay you should carefully check out the seller’s credentials and make sure that they have a lot of good ratings from previous purchasers. Make sure you are covered by eBay’s money back guarantee. Most eBay transactions are completed without problems, but you cannot be too careful when there is a lot of money at stake.

Apple sells discounted Macs that may or may not have been used before through its refurbished store, to grab one of these, see Buy an old Apple Mac and grab a bargain.

Essential tasks with pre-used Macs

Whether you need to do anything with your second-hand Mac depends on where you got it from. Apple’s refurbished MacBooks and iMacs are like new and Apple treats them as new by delivering them in pristine condition and original packaging and prepared like new hardware. You also get a full warranty.

If you bought your pre-used Mac from Apple, then power it up and start using it.

A Mac bought off a friend or from eBay may or may not be ready to use. I wouldn’t trust it. You don’t know what it has been used for or whether it is clean. It could still have the previous user’s files on, adware that they accidentally installed, dodgy software they downloaded from the internet, photos and more.

A clean start is best and you should erase the disk and reinstall macOS. (You should also do this if you are selling your Mac, so that no-one can access your files.)

The Mac should not be password protected and all security should have been disabled before you start. If you try to boot and are prompted for a password, you need to either get the password from the seller or return the Mac because there isn’t anything you can do with it.

Locked Macs are impossible to get into.

Use macOS Recovery

Recovery mode is a special startup for Macs that boots not to the login screen, but to a screen where a special tool called macOS Utilities is available (it used to be called OS X Utilities). This provides access to several tools and they can be used to clean install the system and erase anything that remains from the previous owner.

Reinstall macOS by starting up in recovery mode on the Apple Mac
(That’s a photo from a camera because you can’t screenshot it.)

This feature has been available on most Macs since about 2011. I wouldn’t recommend getting an older Mac than 2011 because you don't want technology that is more than six years out of date. It could have a limited hardware specification.

Press the power button and then hold down Command+R, Option+Command+R or Shift+Option+Command+R to start up. These three options are not quite the same and they affect how the Reinstall macOS menu option works. Here are the differences:

Command+R: This enables you to reinstall the version of macOS that is already installed on the Mac.

Option+Command+R: Use the internet to install the latest version of macOS that is compatible with the Mac.

Shift+Option+Command+R: Use the internet to download the original version of macOS (or OS X) that came with the Mac.

The last option is recommended if the Mac is more than a couple of years old because older versions of macOS (OS X) required less powerful hardware, less disk space, less memory, and so on. It will run better.

You can always upgrade to a newer version of macOS at any time.

Erase the disk

Use Disk Utility from the macOS Utilities to erase the contents of the disk. (See Get to know the new Disk Utility).

  1. Select the Mac’s disk drive and click the Erase button in the toolbar
  2. Set the format to Mac OS Extended (Journaled)
  3. Set the scheme to GUID Partition Map
  4. Click Erase

Format a disk using Disk Utility on the Apple Mac

After erasing the disk you will need to connect to the Wi-Fi network to download macOS. The file can be up to 5GB, so you really need a fairly fast internet connection to do this without spending all day waiting for it to finish downloading.

Connect to the local network using Wi-Fi - you will need to know the password of course.

Select Reinstall macOS to install a fresh copy of the operating system and just follow the instructions. It is straightforward.

Towards the end of the installation, the first-run wizard guides you through logging into iCloud with an Apple ID or creating a new account, and setting up various options.



Add new comment

By submitting this form, you accept the Mollom privacy policy.

Related items you will like...