Upgrading your Mac’s operating system through the Appstore is child’s play, quite literally! OS X has a 4+ age rating on the Mac App Store. That’s like Apple saying ‘Even a five year old can do it.’ Which is probably true, because it’s just like any app install on your phone. Hit GET> Wait for the download > hit ‘INSTALL’ > OK > OK > OK > I Agree > Restart Now > Done.
That’s the easy way. And although there is nothing wrong with it, it’s not necessarily the best option. Especially if you constantly install and uninstall apps that push your Mac to the limits. Not to mention the extensive number of documents – drafts, copies, backups, etc. – that you have been accumulating on your system. All this eventually takes a toll and the Mac starts to show signs of lagging.
But, we have a solution for you, it’s called a Clean Install.
What’s this Clean Install? Never heard of it.
Unlike an ‘Upgrade’ (when all your data and preferences is carried over to the new OS), a clean install is when you format your entire hard disk (clean it) and install the new OS on it. In the former, you have your same old set up, just running under a new OS. In the latter though, you get a Mac that’s brand new and pristine on the inside.
A clean install resets your Mac to the its factory settings. It will help you get the most out of the new OS by using it without any pre-existing bugs or issues. Think of it as the long overdue spring cleaning for your Mac.
Great! Count me in! So how do I do it?
Well, that’s what we’re here for! Follow this simple step-by-step guide to do a clean install of OS X 10.11 El Capitan:
1. Back up your System
As we mentioned before, doing a clean install temporarily wipes out your hard disk (don’t worry, your data isn’t lost). So it’s imperative that you fully back up your entire system to Time Machine.
What’s Time Machine? It’s Apple’s built in software that backs up your data, allowing you to restore it to your system, if something should go wrong. However, depending on Time Machine alone isn’t enough. You should manually copy all data into an external hard disk as well and transfer it back after the install.
Important: Make sure you back up individual apps data as well. For example, iTunes media files, Apple Mail folders, iPhotos / Photos data etc.
2. Download the El Capitan File
Go to the Mac App Store and download the El Capitan file. It’s quite a large file. So be prepared to wait for some time. As soon as the download finishes, the Mac OS X Installer will launch itself automatically. Quit the launcher completely (Press Cmnd + Q). Drag the installer file (Install OS X El Capitan.app) from Downloads to Applications folder and let it sit there for a while.
3. Prepare your USB Stick.
- Get a USB stick. 8 GB will do, but 16 GB is better. Also make sure that you don’t have any data on it, as we will have to format it in the next step.
- Plug in the disk and launch Disk Utility. Use spotlight if you can’t locate the app.
- Select your USB drive in the left hand menu and navigate to the ‘Erase’ tab on top.
- Choose “Mac OS Extended (Journaled)” under the FORMAT drop down menu.
- Choose the name “Untitled”
- Click the ‘Erase’ button at the bottom.
4. Make the USB into a Bootable Disk
Option 1 – The easy way
- Simply download the DiskMaker X app by clicking here and install it.
- The installer will direct you in a couple of easy steps and create the bootable drive for you.
Option: Using Apple’s in-built Terminal software
- Open the Terminal App. It should be in your Utilities folder under Applications. (Again, use spotlight if you can’t find it.)
- In the Terminal app, just copy paste the following code as it is: sudo /Applications/Install OS X El Capitan.app/Contents/Resources/createinstallmedia –volume /Volumes/Untitled –applicationpath /Applications/Install OS X El Capitan.app –nointeraction
- Hit Return (enter). It will ask for your administrative password.
- Type in your admin password and hit Return (enter). Wait for the process to get over and display “Done”.
- That’s it, you now have a bootable OS X El Capitan USB!
5. Boot from your bootable disk
- Restart your Mac.
- While your Mac is booting up, press and hold the OPTION key on your keyboard. The right time to press the key is immediately after you hear the start-up chime on your Mac.
- After a short delay, your Mac will display the OS X Startup Manager, which will display all of your bootable devices. This should include the bootable USB flash drive you just created.
- Use your Mac’s arrow keys to select the OS X El Capitan installer on the USB flash drive, and then press the enter or return key.
- Once the boot process finishes, your Mac will display the OS X Utilities window with the following options:
- Restoring From Time Machine Backup
- Install OS X
- Get Help Online
- Disk Utility
- Select the Disk Utility option, and then click the Continue button.
6. Erase your HDD
NOTE: This step will completely erase your hard disk. So if you did not take a back up of your data, it isn’t too late yet. Exit the installer, restart the Mac normally, Copy your data to an external hard drive and repeat the process.
Before installing the new OS, you need to erase the old OS.
Follow the same steps to format the hard drive that you did for pen drive formatting: Disk Utility > Select Mac HDD > Erase > Mac OS Extended (Journaled)
Once the formatting is complete, you can Quit the Disk Utility app. You will then be returned to the OS X Utilities window.
7. Initiate the Install Process
You are now ready to begin the installation process
- In the OS X Utilities window, select Install OS X, and click the ‘Continue’ button.
- ‘Agree’ to the User License Agreements
- In the next screen choose the HDD you want to install your new OS on. This should be the HDD you just formatted (in case you have multiple hard drives on your Mac).
- Click on ‘Install’. Installation can take anywhere from 1 to 4 hours. During this time, your Mac will restart multiple times. That’s normal.
8. Finish the Install Process
Once the installation is done your Mac will restart for one final time. You will then be guided through the initial start-up process. You will have to select you language, time zone etc, sign into a wifi / ethernet network and sign in using your Apple ID. Pretty basic stuff. Once you finish all this, you will be booted into your Mac.
9.Data and Apps
Just copy back you data. Do not restore the entire system backup as it will defeat the purpose of the entire activity. Use the good old copy-paste style. Install all the apps from Appstore’s Purchases section. Some apps like Skype, Dropbox etc. will need to be downloaded from their respective websites.
That’s it! You are ready to use your fresh and clean Mac with the brand new OS X, El Capitan!