Apple has recently rolled out public beta for macOS High Sierra. And many users have downloaded and installed this fresh version of macOS. But every user is not cut out for this; quite a few want to go back to the old macOS Sierra. If you want to roll back to macOS Sierra, follow this tutorial and downgrade from macOS High Sierra to macOS Sierra.
Before you downgrade from macOS High Sierra to macOS Sierra, you need to take backup of your Mac and create a bootable drive of macOS Sierra.
How to Downgrade from macOS High Sierra to macOS Sierra
Step #1: Take backup of Mac with Time Machine
This process of downgrading from macOS High Sierra may damage or erase your hard disk completely. So if you are working on documents or files, they will be deleted permanently and you won’t be able to recover lost data. You can use Time Machine feature of Mac and take backup on external hard drive. You can also use any cloud based program like DropBox, OneDrive, or iCloud.
Step #2: Create a Bootable Drive of macOS Sierra
You need to download macOS Sierra from Mac App Store before you erase macOS High Sierra from Mac. The OS should be in your purchase list; alternatively, you can search it in the Mac App Store. A copy of macOS Sierra is needed to roll back from macOS High Sierra. When Apple launches final version of macOs High Sierra, macOS Sierra will not be available on the App Store; hence, you need to download Sierra before High Sierra final version is launched.
Note that you need Terminal to make a bootable installer. Many users find it difficult to make changes on Mac with Terminal; in this case, they can use DiskMaker X program.
Step #3: Erase macOS High Sierra
Step #1: Connect your Mac with internet through Wi-Fi or Ethernet.
Step #2: Click on Apple logo from the top left corner.
Step #3: Choose Restart from the drop-down list.
Step #4: Next, you need to press and hold Command+R until your Mac reboots. This will send your Mac into Recovery Mode.
Step #5: When OS X Utilities appear, you should click on Disk Utility.
Step #6: Then hit Continue button.
Step #7: Choose your Startup Disk.
Step #8: Now you should click on Erase tab from the top of the window.
Step #9: Type in the name of the file to be erased (something like macOS High Sierra).
Step #10: From the format list, choose Mac OS Extended (Journaled).
Step #11: Click on Erase button.
Once the process is finished, exit Disk Utility from drop-down list from the top left corner to go back to OS X Utilities window.
Step #4: Reinstall macOS Sierra
Now is the time to reinstall earlier operating system, i.e. your macOS Sierra.
Follow the first three steps as mentioned above.
Step #4: Press and hold Option key while Mac restarts. This action will bring up the option to choose a startup disk.
Step #5: Here, you need to choose macOS Sierra from the list of startup disk options. macOS Sierra will start installing.
Step #6: Next, click on Continue button in macOS Sierra installation dialog box.
The installation of macOS Sierra will be like a standard update. Click on ‘Agree’ to licensing terms before the macOS Sierra reboots on Mac.
Step #5: Restore data from previous macOS Sierra Time Machine Backup
Follow the first three steps as mentioned above: See ‘Erase macOS High Sierra’.
Step #4: Press and hold Command + R when you listen to the startup chime; just keep holding the keys until your Mac reboots.
Step #5: When OS X Utilities window appears, choose Restore from Time Machine Backup.
Step #6: Click on Continue button.
Step #7: Go through the information about restoring from a backup and then click on Continue.
Step #8: Choose Backup source where your Time Machine backup is stored.
Step #9: Now click on Continue.
Step #10: Here, you should choose the most recent backup of macOS Sierra on the drive.
Step #11: Finally, click on Continue.
Mac will start the process of restoring from Time Machine backup and then reboot. Stay relaxed as this process may take some time.