

Reinstalling will cause Spotlight and other background indexing processes to run again which can give the perception that Sierra is running slow but that will resolve itself after indexing has completed.

Your user account, user files, applications, and all data and configurations should be preserved and untouched, only macOS Sierra / macOS High Sierra system software has been reinstalled. Once the reinstall process begins the screen will turn black and an Apple logo with a progress bar will appear, this will give you a loose estimate of how long it will take to reinstall macOS Sierra, but keep in mind it’s not always accurate and the actual installation process can sometimes be faster or slower.Īfter reinstallation has completed, macOS Sierra / High Sierra will automatically boot up as usual.

At the drive selection screen, choose “Macintosh HD” or whatever the name of your hard drive is, this is the drive where macOS Sierra will be reinstalled to, then click on “Continue” or “Unlock” if you use FileVault.Click “Continue” and walk through the setup screen.

