Jul 31, 2018 The machine will start to boot from the USB drive. Way 2: Set a Mac Boot from USB Drive using Startup Disk. When you use Startup Disk preferences to set Mac boot from an external drive, so it’ll boot from that disk until you choose a different one. Here is how: Step 1: Go to Apple menu System Preference, then click Startup Disk. The boot drive selection screen of the Mac mini, showing the original drive, a Time Machine drive, and the replacement SSD Select the external SSD to continue the booting process from the new drive.
Pick the drive you wish to use to start up the Mac. For more advice about installing macOS or Mac OS X read How to update the Mac operating system and How to install old versions of OS X on a Mac. Mar 24, 2020 Connect the USB flash drive or other volume that you're using for the bootable installer. Make sure that it has at least 12GB of available storage and is formatted as Mac OS Extended. Open Terminal, which is in the Utilities folder of your Applications folder. Type or paste one of the following commands in Terminal. May 15, 2020 Connect the USB flash drive to your Mac. Give the flash drive an appropriate name. You can do this by double-clicking the device’s name on the desktop and then typing a new name. We suggest calling the drive elcapitaninstaller, but you can use any name you'd like, provided there are no spaces or special characters. Plug the external drive into the Mac that you want to install the macOS on. Start up the Mac, holding down the Option/Alt key while it is booting up. Your Mac will display the Startup Manager.
If you’re getting ready to install macOS Catalina on your Mac, you have some preparations to make and a few choices to make. While many people just download the new operating system and let the installer do its thing, it’s a much wiser choice to do a bit of housecleaning and preparation before you perform the upgrade.
In this Rocket Yard guide we’re going to exam the two primary ways you can install macOS Catalina, as well as the preparations you should make before you update your Mac.
Types of Installs
Like most versions of the Mac OS, Catalina allows you to perform two types of installs: an upgrade install and a clean install. The same installer is used for both types but the steps involved are a bit different for each.
Clean Install: This type of installation is used when you want to completely remove all traces of a previous version of the OS. The clean install process includes erasing the Mac’s startup drive or the selected destination drive, removing any data it may have held, likely including all of your user data and applications.
The advantage is the ability of a clean install to let you start over, just as if you had just turned your Mac on for the first time.
You can find out more about performing a clean install with the guide:
How to Clean Install macOS Catalina
Upgrade Install: This is the most common type of installation. It allows you to keep all of your current apps, data, and many of the existing operating system settings and preferences. The upgrade install merges the new macOS Catalina with your existing Mac OS.
This is the upgrade method we will cover in this Rocket Yard guide.
Before we begin the upgrade process, a few tips and notes about macOS Catalina and what you need to do to be ready for the install on your Mac.
Compatible Macs: If you’re running macOS Mojave, there’s a good chance your Mac is compatible with Catalina. The main exception is the 2010-2013 Mac Pro, which didn’t make the cut. You can find out more about Mac compatibility in the Rocket Yard guide:
A Complete List of Catalina Compatible Macs
Back Up Your Mac Before You Install
Although an upgrade install shouldn’t directly cause data loss, you should be prepared in case a problem arises when you install Catalina. A backup can allow you to get your Mac back up and running if something goes wrong. It can also serve as protection against the possibility of the new operating system removing any
Another bonus of having a backup is that it can serve as a way to downgrade from macOS Catalina should you discover Catalina isn’t for you, or an app you need no longer works, or your Mac just isn’t performing well with the new OS.
There are two popular backup methods you may consider employing: a Time Machine backup, and creating a clone of the current startup drive. Both are good choices for a backup before you install Catalina (or any new OS). I actually use both methods; a clone is a great way to quickly recover from a failed installation, and Time Machine can not only be used to recover individual files, it can also be used as a downgrade source if you need to return to a previous version of the Mac OS.
Be sure to have a current Time Machine backup, a clone, or both before proceeding.
Be Prepared for Downgrading
There may come a time after installing macOS Catalina that you wish to revert to an earlier version of the Mac OS. This could be for a number of reasons: an important app that doesn’t run under Catalina, an overall performance issue with your Mac and Catalina, or perhaps you just don’t like Catalina and want to go back.
The reason for downgrading really doesn’t matter, but there some things you should do now, before you ever install macOS Catalina, to make the downgrade process as easy as possible.
Be aware that although it’s possible to revert to an earlier version of the Mac OS, you may not be able to make use of specific app data files that could have been converted to new formats by the Catalina version of the application. This has the potential to force you to use older data files from a backup that may not contain all the information you had before beginning the downgrade process.
You can find out more in the article:
macOS Reversion: How to Downgrade from Mojave
The above article is written for the Mojave OS, but the process is the same for downgrading from macOS Catalina.
If you need an earlier macOS installer you can find them here:
Mac Os Upgrade From 10.6.8
- macOS Mojave Installer
- macOS High Sierra Installer
- macOS Sierra Installer
Upgrading Notes
64-Bit: MacOS Catalina supports only 64-bit applications. If you have any 32-bit apps they will not run under Catalina. I recommend checking with the app developer to make sure there’s a 64-bit version of a particular app before you install Catalina.
You can find out more in the Rocket Yard guide:
How to Tell if Your Mac’s Software is 32 or 64-Bit
APFS: macOS Catalina will change your startup drive to one formatted with APFS (Apple File System). The upgrade to APFS is not optional, and the upgrade will occur no matter what type of drive is involved: externals, Fusion, SSDs, or hard drives.
Clean Up: It’s a good idea to take a bit of time to clean up your Mac’s drives, trashing unneeded apps and files. Because you may be removing files, make sure you performed the backups first.
Verify Drives: You may also wish to consider verifying that your storage devices are in good working order. You can use Disk Utility to verify the integrity of a drive. There are also third-party apps that can perform these types of checks.
Upgrade Install macOS Catalina
We’ve gone through the process to get ready to install macOS Catalina, so now it’s time to perform the actual upgrade install. This is one of the easiest installs you can perform. The Catalina installer takes care of the entire process.
Start the upgrade process by quitting any currently running apps you may be using.
If you’re using macOS Mojave:
Launch System Preferences by clicking its icon in the Dock or selecting System Preferences from the Apple menu.
Select the Software Update preference pane.
The Software Update preference pane will appear, and after a few moments, will check for any new operating system updates. Once the check is performed you should see macOS Catalina listed as an available update.
Click or tap the Upgrade Now button to start downloading the Catalina installer.
Jump ahead to the section named Start the Install Process.
If you’re using macOS High Sierra or earlier:
Launch the App Store by clicking its icon in the Dock. You can also find the App Store in the /Applications folder.
Once the App Store opens, select the Featured tab.
You’ll likely find macOS Catalina prominently displayed as the featured item. You may also be able to find it in the Quick Links section on the right-hand side.
Once you have found it, click the macOS Catalina tile or link to open its description.
Select the Download button to start downloading the installer.
Start the Install Process
Once the download is complete, the installer will automatically launch. If you haven’t yet created a current backup, or verified the integrity of your startup drive, you should quit the installer and perform those tasks before proceeding.
When you’re ready you can restart the installer by clicking on the Install macOS Catalina app in the /Applications folder.
The Catalina installer will present its welcome screen. Click or tap the Continue button to proceed.
The software license agreement will be displayed. Click or tap the Agree button.
A sheet will drop down asking you to confirm that you agree with the licensing terms. Click the Agree button.
The current startup drive will be displayed as the target for the upgrade install. If this is correct, click or tap the Install button.
You’ll likely see a dialog box open, explaining that your administrator password is needed in order to continue the install process. Enter your password and click or tap the OK button.
The installation process will start, as the installer copies any needed files to your Mac.
After the files are copied, your Mac will restart.
The installation of macOS Catalina will continue. You should see a dark screen with an Apple logo, along with a status bar indicating the install progress. After a short time, an estimate of the time remaining will be displayed.
Eventually your Mac will display the login screen.
Select your login identity and enter the password.
Post Install
Once you log in to your Mac, you may see a message about your Mac being optimized; this will take a few minutes.
You may see some of the following post install options:
Analytics: You’ll be asked if you wish to participate in providing Apple with analytics that help Apple and its developers improve their products. You can modify these settings later in the Security & Privacy preference pane.
Click the Continue button.
Screen Time: Screen Time configuration options are displayed. You can choose to skip over this step by clicking the Set Up Later text. To proceed, click the Continue button.
Siri:You can enable Siri by placing a checkmark in the Enable Siri box. Click the Continue button when ready.
Theme: You can choose from three themes: the classic Light Mode, Dark Mode, or Auto, which will change between light and dark mode depending on the time of day. Make your choice and click the Continue button.
The setup process is complete and your Mac’s desktop will be displayed.
Your Mac is all set. The new Catalina operating system has been installed and you’re ready to start exploring its many new features. You can find out more about Catalina’s capabilities in the following Rocket Yard guides:
- A First Look at macOS Catalina
- Voice Control Comes to macOS Catalina
- Rocking Out with the Music App in macOS Catalina
- 10 Non-Intrusive Security Changes in macOS Catalina
- macOS Catalina Features: Using Screen Time
- How to Enable Dark Mode in macOS Mojave and Catalina
- How to Use Sidecar to Unite Your Mac and iPad
Let us know what you think about macOS Catalina by posting a comment below.
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You set your Mac or Macbook which disk to start up from when more than one startup disk is connected. This works for USB drives including the NinjaStik
For 2018 to 2020 Macs with the Secure Boot T2 Chip, see the 2020 Macbook Pro Boot from USB instructions.
A “startup disk” is a volume or partition of a drive that contains a bootable operating system.
You can set your Mac to automatically use a specific startup volume, or you can temporarily override this choice at startup.
- From the Apple menu choose System Preferences.
- Click the Startup Disk icon in System Preferences, or choose View > Startup Disk.
- Select your startup disk from the list of available volumes.
The next time you start up or restart your computer, your Mac starts up using the operating system on the selected volume.
Temporarily change your startup disk with Startup Manager
Startup Manager allows you to pick a volume to start from while the computer is starting up.
Use these steps to choose a startup disk with Startup Manager:
- Turn on or restart your Mac.
- Immediately press and hold the Option key. After a few seconds, the Startup Manager appears. If you don’t see the volume you want to use, wait a few moments for Startup Manager to finish scanning connected drives.
- Use your mouse or trackpad, or left and right arrow keys to select the volume you want to use.
- Double-click or press the Return key to start up your Mac from the volume you selected.
If you have an optical drive connected to your computer, you can insert an installation disc to see it in Startup Manager. You can also attach FireWire or USB external hard drives that contain an operating system to add to the list of startup volumes.
Startup Manager automatically adds bootable volumes as you connect them.
Restart in OS X from Boot Camp
Upgrade Mac Os Startup Drivers
If you have started up your Mac in Windows using Boot Camp, you can use the Boot Camp system tray to switch your startup disk default back to OS X.
- In Windows, click the Boot Camp icon in the system tray.
- From the menu that appears, choose Restart in OS X.
Start from OS X Recovery
You can also start your Mac from OS X Recovery or Internet Recovery if your Mac was manufactured after 2011.
To start your Mac from the Recovery System, use these steps:
- Start up or restart your computer.
- Hold down the Command and R keys on your keyboard until you see the Apple logo appear onscreen.
If you don’t see a volume listed
If you don’t see the volume you want to start your computer from, check the following:
- If you’re using an external drive, make sure it’s connected and turned on.
- Make sure you’ve installed an operating system, like OS X or Windows on the drive you’re trying to start from. Volumes that don’t contain a valid operating system aren’t listed in Startup Disk or Startup Manager.
- If you’ve installed an operating system on a drive but it isn’t listed, the volume you’re trying to start from might need repair. If the volume contains OS X, start your computer from OS X Recovery and use Disk Utility to repair the volume, or reinstall OS X on the volume using the Recovery System.
- Depending on the Mac you are using and the version of OS X that is installed, the Recovery System volume (Recovery HD) might not show up in Startup Manager. Press Command-R during startup to start your Mac from the Recovery System.
Mac Os Upgrade To Catalina
For 2018 / 2019 Macbook Pro with the Secure Boot T2 Chip, see the 2018 Macbook Pro Boot from USB instructions.