Pull down the “View” menu in Disk Utility and choose “Show All Devices”.When the “macOS Utilities” screen appears choose “Disk Utility”.Restart the Mac and immediately hold down Command + R keys together to boot into Recovery Mode on the Mac.

Connect the Time Machine backup volume to the Mac if it’s not already attached.How to Downgrade macOS High Sierra to a Prior Mac OS Versionīackup your Mac before beginning this process, it requires erasing the hard drive and removing all data. If you do not have a Time Machine backup made prior to installing macOS High Sierra, of the Mac when on Sierra or El Capitan, then you can not proceed with this approach.

You will want to manually copy and backup your recent work, since any files or work created between installing High Sierra and the last pre-High Sierra backup will be removed in this process. For our purposes here we will be covering a downgrade by erasing, then restoring from a Time Machine backup made prior to installing High Sierra. Downgrading macOS High Sierra is accomplished by formatting the target hard drive, thereby erasing everything on it, then restoring from a prior Time Machine backup, or by formatting and then clean installing a prior version of macOS system software onto the computer, and then manually restoring files from some other backup. Important: Keep in mind there is no official downgrade path for macOS.

There are mixed reports of some Mac users updating to macOS High Sierra and then experiencing a range of problems, from rapid battery life draining, inability for some apps to open, apps crashing, strange performance problems or overall performance degradation, problems with mounting and reading disks, problems with networking connectivity and wi-fi, amongst other issues that could be considered deal breakers. Downgrading system software is probably most appropriate as a last resort or a final troubleshooting method, if some particular problem with High Sierra is making the Mac unusable or incompatible with your workflow. If you do not have a Time Machine backup made with a previous version of Mac OS, this will not be possible to follow.įor most users, they should not downgrade from macOS High Sierra. The downgrade method we’ll cover here uses a Time Machine backup to restore to a prior version of macOS and downgrade macOS High Sierra 10.13.

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