During installation, it might restart and show a progress bar or blank screen several times. Please allow installation to complete without putting your Mac to sleep or closing its lid. Open that app from your Applications folder to begin installing the operating system. It installs an app named Install Mac OS X Lion. Safari downloads the following installer as a disk image named InstallMacOSX.dmg. To upgrade from Mac OS X Snow Leopard 10.6, download and install Mac OS X 10.6.8 Update Combo v1.1 followed by Mac OS X Lion 10.7.5. If you are unable to upgrade, see How to create a bootable installer for Mac OS X Lion below. To upgrade from Mac OS X Tiger 10.4 or Mac OS X Leopard 10.5, first upgrade to Mac OS X Snow Leopard 10.6, then upgrade to Mac OS X Lion 10.7. * If your Mac shipped with OS X Mountain Lion 10.8 or later, it cannot be downgraded to Mac OS X Lion 10.7. Mac Pro (Mid 2010) | 10.14.6 with recommended Metal-capable graphics cards.Mac Pro (Mid 2012)* | 10.14.6 with recommended Metal-capable graphics cards.See the Technical Specifications for the full list of requirements. The latest supported software version is noted next to each model.

You can install Mac OS X Lion on any of these Macs.

Mac OS X Snow Leopard 10.6.6 or later or Mac OS X Lion 10.7 already installed.

Mac OS X Lion 10.7 is available for older systems that are not compatible with the latest version of macOS.

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