This guide provides step-by-step instructions for creating a portable Windows USB drive compatible with Intel-based Macs, enabling you to run Windows on the Mac computer to complete the Windows-dependent work.
I have a late 2016 MacBook Pro with macOS and Windows 10 Pro dual systems installed on it, so far so good, but I only use Windows 10 Pro to play some games that can't be run on macOS. Now I'm trying to get rid of my Boot Camp installation, because of low space on main SSD drive. I noticed that WinToUSB can install Windows to a USB drive, can the Windows USB drive created by WinToUSB be started from a Mac computer? How do I make it? Could let me know step by step for using your tool Hasleo WinToUSB.
The portable Windows (Windows To Go) USB drive created by Hasleo WinToUSB can boot on Intel-based Macs (excluding Apple Silicon M1/M2/M3/M4), though boot success rates may be not 100%. Understanding the causes of boot failures can help avoid these issues.
* Tips:
1. Not all Mac computers use Intel CPUs (Newer Mac computers use Apple Silicon M1/M2/M3/M4 chips), so you should verify your Mac uses an Intel CPU.
2. Apple selected Intel's Extensible Firmware Interface (EFI) as its UEFI/BIOS replacement, replacing the Open Firmware used in PowerPC systems. Therefore, to successfully boot Windows on Intel-based Macs, the portable Windows USB drive must support EFI boot mode.
3. To boot Windows on (U)EFI computers, the Windows version must match the PC architecture: a 64-bit (U)EFI computer supports only 64-bit versions of Windows and a 32-bit (U)EFI computer supports only 32-bit versions of Windows. Intel-based Macs utilize a 64-bit Intel CPU, therefore ensure you use a 64-bit Windows to create portable Windows.
Step 1. Download Boot Camp Windows Support Software for Windows To Go: How to Download Boot Camp Windows Support Software for Windows To Go?
Step 2. Copy the Boot Camp Support Software (downloaded in the previous step) to the WinToUSB-installed computer, then connect the external hard drive to the computer. Run Hasleo WinToUSB and click the "Windows To Go USB" option.
Step 3. Click "Select installation source" → "Browse image file". Then choose the Windows Server installation ISO file from the dialog box as your source. Alternatively, select a CD/DVD drive with Windows Server installation media.
Step 4. Hasleo WinToUSB scans for and lists installable operating systems. Select your target Windows edition to proceed with the installation.
Step 5. Click "Select destination drive", then choose the target drive from the pop-up list. If Hasleo WinToUSB fails to detect the drive, click the 
button to initiate drive recognition.
Step 6. Select your preferred partition scheme and installation mode. Specify the directory of the additional drivers as the save path of Boot Camp Support Software and enable BitLocker encryption for the Windows To Go external hard drive if you want, then click "Proceed".
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Step 7. After clicking "Proceed", a confirmation dialog will appear asking whether to continue formatting the drive. Click "Yes" if you accept the operation.
Step 8. After clicking "Yes", WinToUSB initiates Windows installation on the destination drive.
Step 9. It takes several minutes to install. After installation, safely unplug the USB drive from the Windows computer. Connect the drive to the target Mac. For Macs with only USB-C ports, a USB-C to USB adapter is required to connect the USB device.
Step 10. Power on the Mac and immediately hold the Option key, then select the USB drive and press Return to boot from it. Pleasse note that the USB drive typically appears as "EFI boot" or "Windows" in the boot menu.
Step 11. A standard Windows installation requires completing all setup steps during the first boot. Should the Mac's built-in keyboard/touchpad fail during installation, connect an external USB keyboard or mouse to complete the installation. Afterward, you can install Windows Support Software (Boot Camp drivers), applications, and copy files, etc.
Having learned to install and run portable Windows (Windows To Go) on Intel-based Macs with the best free Windows To Go Creator Hasleo WinToUSB, you may also use WinToUSB to clone existing Boot Camp Windows installations to USB drives and then boot the Windows from that USB on an Intel Mac.
