Quick Answer: How to Reinstall Mac Os X?

Step 4: Reinstall a clean Mac operating system

• Restart your Mac.
• While the startup disc is waking up, hold down the Command+R keys simultaneously.
• Click on Reinstall macOS (or Reinstall OS X where applicable) to reinstall the operating system that came with your Mac.
• Click on Continue.

The procedure is as follows:

• Turn your Mac on, while holding the CMD + R keys down.
• Select “Disk Utility” and click on Continue.
• Select the startup disk and go to the Erase Tab.
• Select the Mac OS Extended (Journaled), give a name to your disk and click on Erase.
• Disk Utility > Quit Disk Utility.

Select your startup drive on the left (typically Macintosh HD), switch to the Erase tab and choose Mac OS Extended (Journaled) from the Format drop-down menu. Select Erase and then confirm your choice. Quit out of the Disk Utility app, and this time choose Reinstall OS X and Continue.Nothing works? Reinstall OS X

• Make sure your power adapter is plugged in.
• Restart your Mac holding down the Command and R keys.
• Choose a network from the Wi-Fi menu or connect an Ethernet cable.
• Select Disk Utility, then click Continue.
• Select your startup disk on the left, then click the Erase tab.

How to restore your hard drive from a Time Machine backup

• Power up your Mac and hold down the Command and R keys to enter the macOS Recovery Partition.
• Select Restore from Time Machine Backup and click Continue.
• Read the info on the Restore Your System page and click Continue.

Boot from one of those, and you simply wipe the FileVault drive. You’ll need to reinstall macOS entirely on that drive to wipe out the Recovery Disk settings. Use Internet Recovery. At startup, hold down Command-Option-R, and you can select Reinstall macOS.

How do I do a clean install of OSX?

So, let us begin.

1. Step 1: Clean up your Mac.
2. Step 2: Back up your data.
3. Step 3: Clean Install macOS Sierra on your startup disk.
4. Step 1: Erase your non-startup drive.
5. Step 2: Download the macOS Sierra Installer from the Mac App Store.
6. Step 3: Start the Installation of macOS Sierra on the Non-startup drive.

How do I restore my Mac to High Sierra?

Click on the Apple menu and choose Restart. Hold down Command+Option+Shift+R to boot into recovery mode. Note, you can also boot into Recovery mode by pressing Command+R. However, adding Option+Shift will allow you to reinstall High Sierra, if your Mac came with it installed.