Use Boot Camp Assistant to install Windows 8 on Mac
You need support software (drivers) installed with Boot Camp to use Windows 8.1. This software is automatically downloaded when you use Boot Camp Assistant. Boot Camp supports 64-bit versions of Windows 8.1 when used with a supported Mac.
Windows 8.1 is available from Microsoft as an ISO file, or an installation DVD. You need an ISO file of the 64-bit full install version of the Windows 8.1 installer to install Windows on your Mac. If you don't have an ISO file, you can use Disk Utility to make one from your Windows installation DVD.
Use these steps if you're installing Windows on your Mac for the first time.
Use the list at the end of this article to make sure you have a Mac that supports Windows 8.1.
Check for software updates to make sure OS X, your Mac firmware, and Boot Camp Assistant are up to date.
Open Boot Camp Assistant from the Utilities folder (or use Spotlight to find it).
Use Boot Camp Assistant to install a new copy of Windows.
If you have an earlier version of Windows already installed on your Mac, you can use these steps to upgrade to Windows 8.1.
You can upgrade existing 64-bit installations of Windows 7 or 8 to Windows 8.1. You need at least 10 GB of free space on your Windows partition.
When your Mac desktop appears, choose App Store from the Apple menu. Click the Updates tab in the App Store window to check for software updates. Make sure OS X and your Mac firmware are up to date.
Start your Mac from the version of Windows you currently have installed.
Open Apple Software Update for Windows and install available updates.
Use the Windows installer to upgrade Windows.
After installation is complete, open Apple Software Update for Windows again and install available updates to make sure the Windows Support Software (drivers) for Boot Camp are up to date. As part of driver installation, your Mac might restart one or more times.
If you see the message “Uninstall USB 3.0 eXtensible Host Controller Driver” during installation, don't uninstall the driver. Instead, see Windows 8: "Uninstall the USB 3.0 eXtensible Host Controller Driver" alert when upgrading from Windows 7.
If you have an existing 32-bit installation of Windows on your Mac, you'll need to back up your important files so that you can remove the existing Windows partition and install a 64 bit version of Windows.
Back up any important files from your Windows partition.
Use Boot Camp Assistant to remove the existing Windows partition.
Then, use Boot Camp Assistant to install a 64-bit version of Windows 8.1 on your Mac.
After you're finished installing Windows, copy your important files back to your Windows drive.
Boot Camp 6 includes support for the following features of your Mac in Windows 8.1.
USB 3
Thunderbolt
built-in SD or SDXC card slot
built-in or USB Apple SuperDrive
your Apple keyboard, trackpad, and mouse
You can install Windows 8.1 on an internal drive in your Mac. Boot Camp Assistant helps you create a partition on your drive that's compatible with Windows. When you install Windows on a Mac that includes a Fusion Drive, the Windows partition is created on the mechanical hard drive part of the Fusion Drive (not the SSD). Microsoft BitLocker is not compatible with Boot Camp volumes.
After you install Windows, you can install the latest version of iTunes for Windows to listen to your music or play videos. You'll need to authorize iTunes in Windows to play music or videos you've purchased from the iTunes Store.
If some features aren't working when you start your Mac from Windows 8.1, try reinstalling Boot Camp support software using Boot Camp Assistant.
The following Mac models support 64-bit versions of Windows 8.1 when installed using Boot Camp. Use About This Mac to see which Mac you have, then check this list to see if it supports Windows 8.1.
MacBook Pro (Retina, 15-inch, Mid 2015)
MacBook Pro (Retina, 13-inch, Early 2015)
MacBook Pro (Retina, 15-inch, Mid 2014)
MacBook Pro (Retina, 13-inch, Mid 2014)
MacBook Pro (Retina, 15-inch, Late 2013)
MacBook Pro (Retina, 13-inch, Late 2013)
MacBook Pro (Retina, 15-inch, Early 2013)
MacBook Pro (Retina, 13-inch, Early 2013)
MacBook Pro (Retina, 13-inch, Late 2012)
MacBook Pro (Retina, Mid 2012)
MacBook Pro (13-inch, Mid 2012)
MacBook Pro (15-inch, Mid 2012)
MacBook Pro (17-inch, Late 2011)
MacBook Pro (17-inch, Early 2011)
MacBook Pro (15-inch, Late 2011)
MacBook Pro (15-inch, Early 2011)
MacBook Pro (13-inch, Late 2011)
MacBook Pro (13-inch, Early 2011)
MacBook Pro (15-inch, Mid 2010)
MacBook Pro (17-inch, Mid 2010)
MacBook Air (13-inch, Early 2015)
MacBook Air (11-inch, Early 2015)
MacBook Air (13-inch, Early 2014)
MacBook Air (11-inch, Early 2014)
MacBook Air (13-inch, Mid 2013)
MacBook Air (11-inch, Mid 2013)
MacBook Air (13-inch, Mid 2012)
MacBook Air (11-inch, Mid 2012)
MacBook Air (13-inch, Mid 2011)
MacBook Air (11-inch, Mid 2011)
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