How do I install an older version of Mac OS X?

Here are the steps Apple describes:

1. Start up your Mac pressing Shift-Option/Alt-Command-R.
2. Once you see the macOS Utilities screen choose the Reinstall macOS option.
3. Click Continue and follow the on-screen instructions.
4. Select your startup disk and click Install.
5. Your Mac will restart once the installation is complete.

Can you download an older version of Mac?

You can download most older versions of macOS using the Mac App Store or direct links to Apple’s website. Unfortunately, Apple doesn’t index the Mac App Store entries so that you can search for them in the app.

How do I downgrade OS X?

To downgrade macOS via Time Machine, plug your Time Machine backup drive into your Mac, then restart the computer. As soon as the screen goes dark, hold down the ‘Command’ + ‘R’ keys until the Apple logo appears. Next, choose the option, ‘Restore From Time Machine Backup’ and click ‘Continue’.

How do I install an older version of iOS?

You’ll need to perform these steps on a Mac or PC.

1. Select your device.
2. Select the version of iOS you wish to download.
3. Click the Download button.
4. Hold down Shift (PC) or Option (Mac) and click the Restore button.
5. Find the IPSW file that you downloaded earlier, select it and click Open.
6. Click Restore.

How do I install an older version of an external hard drive Mac?

Install older OS X onto an external drive Start your Mac holding down Command + R. Prepare a clean external drive (at least 10 GB of storage). Within OS X Utilities, choose Reinstall OS X. Select external drive as a source.

Can I install OSX on external hard drive?

Luckily you don’t have to install the OS update on your Mac at all – you can install it on an external drive instead. Installing the Mac operating system on an external drive is the safest way to get a good look at a new OS without changing anything on your Mac.

Can I install unsigned iOS?

Yes, you can restore your iOS device to an unsigned IPSW firmware, but not in the traditional way. To upgrade or downgrade to a previous iOS firmware that has stopped being signed by Apple, part of the requirements are a third-party restore app, the destination unsigned iOS IPSW file, and its SHSH blob file.

How do I download a specific version of iOS?

By alt-clicking on the update-button in iTunes you are able to select a specific package you want to update from. Select you downloaded package and wait until the software ist installed on the phone. You should be able to install the most recent version of iOS for your iPhone model this way.