Tutorial to install Windows 10 (8 or 7) - UEFI Bootcamp - into a GPT external HDD volume


In this thread, let’s together install Windows 10, Windows 8 or Windows 7 at your demand (UEFI Bootcamp) into a GPT External Hard Driver.


The following instruction we deal with Windows 8.1 at an example.
1. Format the external HDD volume to GPT.
There should be 3 ways:
+, Use Disk Utility in Mac OS X (use GUID option). The data is lost if using this method.
+, Use some similar softwares in Windows: AOMEI PARTITION SERVER 5.5, MiniTool Partition Wizard Professional 8.1. You do not loose Data using this method.
+, Using command lines.

CMD with admin



Select disk * (you should select the right disk)
List volume
Select volume * (select the right volume you want to install Windows into)


2. Mount Win8.1.iso or Plug the Windows 10 (7, 8 or 8.1) Bootable UEFI USB installation

3.Install Windows into NTFS External Volume
+, Navigate to Windows Easy Install\Windows Easy Install (downloaded by the given link)
+, Open installer.cmd with administrator.

+, Enter —> Choose Sources of Mount Windows.ISO or in the USB —> Select Install.win

+, Select the corresponding Windows version.
+, Select the right volume (F is my case).
+, Choose F one more time.

+, Next, the program will ask if it is USB. Just press Y (yes).

4. In your Mac OS X, Install rEFit

  • During the Windows installing time, we can take time to install rEFit in Mac OS X.
  • Run rEFIt-0.12.dmg, click on rEFIt.mpkg.
  • Copy efi foler into Macintosh.
  • Open Terminal then type:

cd /efi/refit

5. Fix boot error (if happened)
+, Plug the external HDD to boot.
+, Select Windows volume, if you are booted to Windows, Congrats!

  • If you see the error on the screen like you are asked to insert the Windows DVD to repair, just plug the USB prepared, then boot to USB —> Choose Repair Windows.
    6. You are now ready to install Bootcamp into the Windows.

Leave a comment for facing any problems.