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Reinstall Os X Yosemite

Oct 10, 2014 Near the center of the window, select the Format drop-down list and select “Mac OS X Extended (Journaled)” as the type. Click Erase (this will erase your main drive!) and allow some time for the drive to format. When it’s finished, close out Disk Utility and select “ReInstall OS X” from the menu. It will ask for your Mac App Store password to redownload OS X Yosemite.

Start up from macOS Recovery

Once you’ve done that, here’s how to install, reinstall, or upgrade Yosemite, step by step: Boot from your Recovery HD partition by restarting your Mac while holding down the Command+R keys. The OS X Utilities window appears. Select Reinstall OS X, and click Continue. The OS X Yosemite splash screen appears. Use How to get old versions of macOS to download an installer for OS X Yosemite while running on Yosemite. Run the installer and it will install the full installer to /Applications/Install OS X Yosemite.app. Use the command line from How to create a bootable installer for macOS substitution El Capitan for Yosemite in the El Capitan instructions. Steps to take to reinstall Safari: Remove Safari with Clean My Mac (or something similar, simply dragging it to the trash doesn't work) Ask a friend/colleague (someone you trust not to have adapted the file) to upload his Safari to a server or dropbox (or something similar) Download the just-uploaded Safari. Drag it from your download-folder to.

Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:

Apple silicon

Turn on your Mac and continue to press and hold the power button until you see the startup options window. Click the gear icon labeled Options, then click Continue.

Intel processor

Make sure that your Mac has a connection to the internet. Then turn on your Mac and immediately press and hold Command (⌘)-R until you see an Apple logo or other image.

If you're asked to select a user you know the password for, select the user, click Next, then enter their administrator password.

Reinstall macOS

Select Reinstall macOS from the utilities window in macOS Recovery, then click Continue and follow the onscreen instructions.

Reinstall Os X Yosemite No Disk

Follow these guidelines during installation:

  • If the installer asks to unlock your disk, enter the password you use to log in to your Mac.
  • If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.
  • If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.
  • Allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.
Pro

After installation is complete, your Mac might restart to a setup assistant. If you're selling, trading in, or giving away your Mac, press Command-Q to quit the assistant without completing setup. Then click Shut Down. When the new owner starts up the Mac, they can use their own information to complete setup.

Other macOS installation options

When you install macOS from Recovery, you get the current version of the most recently installed macOS, with some exceptions:

  • On an Intel-based Mac: If you use Shift-Option-Command-R during startup, you're offered the macOS that came with your Mac, or the closest version still available. If you use Option-Command-R during startup, in most cases you're offered the latest macOS that is compatible with your Mac. Otherwise you're offered the macOS that came with your Mac, or the closest version still available.
  • If the Mac logic board was just replaced, you may be offered only the latest macOS that is compatible with your Mac. If you just erased your entire startup disk, you may be offered only the macOS that came with your Mac, or the closest version still available.

You can also use these methods to install macOS, if the macOS is compatible with your Mac:

Install Os X Yosemite Download

  • Use the App Store to download and install the latest macOS.
  • Use the App Store or a web browser to download and install an earlier macOS.
  • Use a USB flash drive or other secondary volume to create a bootable installer.