To get the latest features and maintain the security, stability, compatibility, and performance of your Mac, it's important to keep your software up to date. Apple recommends that you always use the latest macOS that is compatible with your Mac.
Learn how to upgrade to macOS Big Sur, the latest version of macOS.
UEFI requires intervention because EFI firmware on the Mac's motherboard cant find valid OS-specific EFI boot firmware in the standard location on disk. However, assuming you have a macOS recovery partition on that disk, it should contain a copy of boot.efi (macOS-specific boot firmware) that you can boot into the OS with.
Mac OS X Mountain Lion Overview. OS X is an operating system designed and marketed by Apple Inc. For its Mac series of computers. The OS X Mountain Lion is the ninth version of the operating system, replacing its predecessor; the Mac OS X Lion. The change in the name signifies an update, which is now a regular feature of Apple’s software policy. The macOS High Sierra 10.13.6 Update adds AirPlay 2 multiroom audio support for iTunes and improves the stability and security of your Mac. This update is recommended for all users.
Check compatibility
- Lets get on with the Mac OS High Sierra Download! This is handy if you want to do a fresh install of macOS if something has gone wrong with your correction version of macOS or OSX. If you have any trouble with downloading the file then please leave a message here and we will get it sorted.
- In 2020, macOS High Sierra is available on both Mac computers and Windows computers. Both the segment users can get the benefit of using the same software. After macOS High Sierra macOS Mojave was introduced but it wasn’t as popular as High Sierra. According to folks, macOS High Sierra does have better performance than traditional macOS.
If a macOS installer can't be used on your Mac, the installer will let you know. For example, it might say that it's too old to be opened on this version of macOS, or that your Mac doesn't have enough free storage space for the installation.
To confirm compatibility before downloading, check the minimum requirements for macOS Catalina, Mojave, High Sierra, Sierra, El Capitan, or Yosemite. You can also find compatibility information on the product-ID page for MacBook Pro, MacBook Air, MacBook, iMac, Mac mini, or Mac Pro.
Make a backup
Before installing, it’s a good idea to back up your Mac. Time Machine makes it simple, and other backup methods are also available. Learn how to back up your Mac.
Download macOS
It takes time to download and install macOS, so make sure that you're plugged into AC power and have a reliable internet connection.
Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.
- macOS Catalina 10.15 can upgrade Mojave, High Sierra, Sierra, El Capitan, Yosemite, Mavericks
- macOS Mojave 10.14 can upgrade High Sierra, Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion
- macOS High Sierra 10.13 can upgrade Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion
Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to begin installing the operating system.
- macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion, or Lion
- OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion, or Snow Leopard
- OS X Yosemite 10.10can upgrade Mavericks, Mountain Lion, Lion, or Snow Leopard
Install macOS
Follow the onscreen instructions in the installer. It might be easiest to begin installation in the evening so that it can complete overnight, if needed.
Get Macos High Sierra Installer
If the installer asks for permission to install a helper tool, enter the administrator name and password that you use to log in to your Mac, then click Add Helper.
Please allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart, show a progress bar, or show a blank screen several times as it installs macOS and related firmware updates.
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Where To Get Mac Os High Sierra
You might also be able to use macOS Recovery to reinstall the macOS you're using now, upgrade to the latest compatible macOS, or install the macOS that came with your Mac.