The Windows installer is UEFI booted from the USB flash drive.The Windows files provided by Apple copied to the USB flash drive. The Windows files provide by Microsoft are copied to both the internal drive and an USB flash drive.This is referred to as hybrid partitioning, which is a requirement when macOS and a BIOS booting Windows are installed. Care is taken to insured that at least the partition where Windows is to reside is recorded in the legacy Master Boot Record (MBR) partition table.A partition is created for Windows on the internal drive.This accepted answer requires the Mac to have firmware upgrades provided when High Sierra is first installed. One method, which was explicitly tested using a iMac12,1 and Windows 10 version 21H1, is given as the accepted answer to the Ask Different question ' How to install Windows 10 into a 2011 iMac without using the Boot Camp Assistant, an optical (DVD) drive or third party tools?'. There have been posts here at Ask Difference and elsewhere explaining how to install Windows 10 on Macs where the Boot Camp Assist is either not utilized or only partially utilized. The rest of this answer addresses how to do a clean install of Widows 10 version 21H1 without having to upgrade from a previous version. The Windows drivers provided by Apple work best when Windows is installed to BIOS boot.Īttempting an UEFI booting installation of Windows on a iMac12,1 generally results in either complete failure or partial lost of use of hardware. The USB flash drive is suppose to just have the Boot Camp Support Software or Windows Support Software. The Boot Camp Assistant is designed to use a Windows installation DVD to install Windows on your model Mac. Once installed, you should be able to upgrade to Windows 10 version 21H1. The Boot Camp Assistant can be used to installed 64 bit BIOS booting Windows 7 through Windows 8.1.

Install windows 10 on macbook air 2011