In addition, be sure that you know all of your online account passwords and logins - for this, a password manager like 1Password can be very useful. Make sure that you have access to all installation media for your apps (developer websites, Mac App Store, DVD or CD), and it’s a good idea to make a Note of all apps that you wish to re-install. Clean installs are also useful if a software or system software update has somehow trashed your existing operating system or if you have replaced a hard drive.īe sure you have plenty of time available to complete the complete install, as it can sometimes take as much as a day to go through all the steps.Īs noted, we’re going to completely erase everything on the Mac. In many cases, a clean install can improve the performance of a sluggish Mac. The idea behind a clean install is to start with a completely bare machine, getting rid of any old data, files, preferences, settings, old drivers, apps you no longer use, and so on. In this post, we’ll describe how to do a clean install of macOS 10.13 High Sierra.īefore we get started, make a decision as to whether you want to do a regular update or a clean install, because a regular update is much easier to perform than a clean install. What’s a clean install? That means that the hard drive is erased completely and reformatted, which removes not only the current Mac operating system but all data, files, applications, you name it… Just think of it as a brand new computer having the operating system installed on it for the first time.

Sometimes it’s a good idea to do a clean install of a new Mac operating system version.

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