( will list your partitions on the selected disk ) ( will list your drives ) Now select your Windows drive ( for example “ 0 ”) ( note down your Windows partition letter. ( this is the Windows partition manager ) At “Advanced options” select “Command Prompt”.Boot from the Windows installer USB, click “Repair your computer”.Right click, Shrink your Windows drive to create unallocated space for macOS (do not create a new partition yet).Win + R, open “diskmgmt.msc” (Create and format hard disk partitions).So the problem is that the Windows EFI is 100 MB, not 200 MB so the macOS Disk Utility will fail when creating the new APFS partition for macOS, we need to resize the EFI first Install macOS when Windows 10/11 is already installed A GPT-UEFI Windows 10 or 11 installer USBġ.Important note: This will ONLY work if your system is in GPT (GUID)-UEFI mode (not MBR-Legacy) Install macOS when Windows 10/11 is already installed.When you have an empty disk and want to install the two OS When you have macOS installed and want to install Windows on a new partition When you have Windows installed first and don't want to lose all your data (should work with Windows 8 and earlier versions of macOS but they're untested) All-in-One Dual-Boot Guide for all scenarios
