How To Perform A Clean Os Install On Mac Without Cd Drive

Sometimes information technology'south a good idea to do a clean install of a new Mac operating system version. What'southward a clean install? That means that the difficult bulldoze is erased completely and reformatted, which removes not just the current Mac operating organisation just all information, files, applications, you name it… Just retrieve of it equally a brand new computer having the operating system installed on it for the first time. In this postal service, we'll describe how to do a clean install of macOS 10.xiii High Sierra.

Reasons to Perform a Make clean Install
Before we become started, make a decision every bit to whether you want to do a regular update or a clean install, because a regular update is much easier to perform than a make clean install.

The thought behind a clean install is to start with a completely bare automobile, getting rid of whatsoever old information, files, preferences, settings, former drivers, apps you no longer use, and so on. In many cases, a clean install can improve the functioning of a sluggish Mac. Clean installs are besides useful if a software or system software update has somehow trashed your existing operating system or if y'all take replaced a hard drive.

Exist sure y'all have enough of time available to complete the consummate install, as it tin can sometimes accept equally much as a day to go through all the steps.

Step 1: Backup Your Mac
As noted, nosotros're going to completely erase everything on the Mac. Make sure that you accept access to all installation media for your apps (developer websites, Mac App Store, DVD or CD), and it's a good thought to make a Note of all apps that y'all wish to re-install. In addition, exist sure that you lot know all of your online account passwords and logins — for this, a password manager like 1Password tin exist very useful.

It's very useful to also accept copies of all of your license data for Mac apps, since those that require a license or activation will need to be set up after your clean install.

At present, what kind of backup to you lot want to exercise? A Time Machine backup of your entire organisation is quite acceptable, or you lot tin use an app like Carbon Copy Cloner or SuperDuper! to create a bootable clone of your Mac.

For those really of import files, such every bit important documents, photos, videos, so on, you may want to make a separate fill-in onto other media or to a deject service like iCloud Drive or Dropbox.

Do Not become farther without making a backup. Remember, your Mac volition be completely erased and if yous have not copied your information to another location, yous will lose it.

Stride 2: Create a Bootable macOS High Sierra Installer
Yous tin create a bootable macOS High Sierra install disk by knowing only what Terminal commands to use. Withal, there'south an easy way to practise this pace, and that's to utilise DiskMaker X seven. We just published a step-by-step process for creating your bootable macOS High Sierra installer using this free application, and then take time to read the procedure and to make your installer disk

When you're done with steps 1 and 2, you can proceed to the scary role — erasing and reformatting your Mac's kick bulldoze.

Footstep 3: Erase and Reformat the Mac's Kicking Drive
Brand sure that the bootable macOS High Sierra installer you lot simply created is continued to your Mac, whether it's a USB flash bulldoze or an external hard disk. Reboot your Mac, and agree down the Option/Alt key on the keyboard until the macOS Startup Manager Screen appears. It looks something like this:

**macOS Startup Manager, showing all internal and external drives**

While the image above shows the Mac'southward kick drive "Macintosh Hard disk" as selected for boot, we do not desire to use that drive; instead, employ the arrow keys or your trackpad to point the cursor at "Install macOS High Sierra", then press Return.

The Mac boots off of the Loftier Sierra installer into the macOS Utilities screen (image below is from a photograph of an actual Mac display):

**macOS Utilities, with Disk Utility highlighted**

Click Continue to keep to Disk Utility. Once Disk Utility is on your screen, select your boot bulldoze (it's unremarkably named Macintosh HD, equally in the screenshot below) then click the Erase button in the carte bar.

Select the boot drive (Macintosh HD) and click Erase in the menu bar — **Select the boot drive (Macintosh Hd) and click Erase in the carte du jour bar**

When promoted, select "Mac Os Extended (Journaled) as the format type, with GUID Partition Map as the scheme. Note that if your Mac can be converted to the new APFS file system, it will happen during the macOS High Sierra installation. At this point, information technology'southward perfectly fine to use the "old" format defaults.

Once y'all've selected the format type and scheme, click the Erase push button. Recall, this erases everything on the Mac, so if you ignored the repeated reminders earlier to accept complete backups of your Mac, you're going to lose everything.

Equally soon every bit the drive formatting is completed, quit out of Deejay Utility. You will be returned to the macOS Utilities screen.

Pace 4: Install macOS High Sierra
The second item from the pinnacle of the macOS Utilities screen is "Install macOS". Select this particular by clicking on it, then click on Proceed. In the installer screen, select "Macintosh Hard disk drive" (or whatever your boot bulldoze is actually named) as the disk for macOS High Sierra to be installed on.

The installation of macOS High Sierra will take a while, and when information technology'southward completed the Mac reboots and goes through the setup procedure that is familiar to anyone who has owned a new Mac. You lot're asked to enter your Apple tree ID, create a user account, and setup iCloud. At this point, you have a clean version of macOS High Sierra on your Mac.

Step 5: Restore Information, Files and Apps
This step is probably the most fourth dimension-consuming 1 in the entire clean install process. Copy your document files to the newly-cleaned Mac from an external drive or cloud service — note that if you have chosen to relieve all of your documents in your iCloud Bulldoze, there'due south no need to perform this step.

App reinstalls are done rapidly from the Mac App Store, and installers for other apps can be downloaded from the developers.

You may need to prepare up your email accounts again, particularly for accounts that are on servers that aren't associated with Apple tree or Google. If yous use a cloud backup service similar Backblaze, be sure to set upward the Mac client again so that you can begin your backups as shortly as possible.

That's information technology! You now have a squeaky clean installation of macOS High Sierra on your Mac. You lot may find, every bit I did when I installed macOS High Sierra on my iMac using this procedure, that you lot suddenly take a lot more than space available on your figurer and that it runs a bit more than smoothly. Permit us know how your clean install went by leaving a note in the comments department below.

Steve has been writing almost Apple tree products since 1986, starting on a bulletin board organization, creating the start of his many Apple tree-related websites in 1994, joining the staff of The Unofficial Apple Blog in 2008, and founding Apple World Today in 2015. He's semi-retired, loves to campsite and take photos, and is an FAA-licensed drone pilot.