Introduction: Installing Windows on External Drive With Mac Partition on Mac

About: Get creative

If you have bought something like a baseline MacBook pro and saved a little cash, but then soon hit with the storage issue when trying to install windows using Bootcamp

We all know that 128 gb is not enought these so we might have bought something like a an external HDD for some additional storage.

In this tutorial is going to tell u how to install windows on to the external drive and save precious 32gb(minimum for windows 10) from your hard drive

This tutorial is based on

But I will tell how to add another mac (HFS+) partition that can be used to install mac os apps if you don't need them



External HDD or SSD(if you are rich?)

windows pc(better to have a real windows pc, if not the link above describes how to use a virtual machine)

windows 10 iso(get it from Microsofts website or refer the link above)


And little patience and persistence to try again if something goes wrong

Make sure to backup anything on your external drive, I can assure u one thing it won't be easy to get it back to get it back once this done, I would also recommend to backup you do a full-time machine backup if you have

Step 1: Preparation of the External Drive

Plug the external drive into your mac and select the Disk utility app

You will see your drive listed on the side panel

Select your drive and select Erase and a list of options will pop up

  1. Select Format: Mac OS journaled
  2. Scheme: GUID Partition Map
  3. Rename the drive say"Bootcamp"
  4. Select Erase

Now the drive will be formatted

  1. Now plug the drive to windows machine
  2. type partition into the start menu and select 'Create and format Hard Disk partitions'
  3. You should see the drive listed
  4. Right click and the "Bootcamp" partition and select 'Delete volume'
  5. Then the partition will be deleted and its space will be marked as Unallocated space
  6. Right click on 'New simple volume'
  7. Give the size of the space u wont to give to windows partition
  8. and select NTFS
  9. U cannot change this after installing windows
  10. Now after the partition is created, u can allocate the rest of the unallocated space for the mac partition
  11. Right-click on the unallocated space, 'New simple volume' now u can give the amount of space for mac partition name the partition say "Time machine"
  12. Select FAT32 or NTFS(it doesn't matter) we will format out this partition in mac ?
  13. Eject the disk and plug it back into mac and select the disk utility again and then select "Time machine"
  14. Select the Erase button , and Select Format:'Mac OS journaled'

Now the disk is prepared

Step 2: Getting MacBook or IMac Drivers for Windows

  1. Select the 'Download windows Support software
  2. Select a download location
  3. Once the download it complete u can copy the files to windows partition after installation

Step 3: Installing Windows

Plug your drive back into windows again and launch the WinToUSB software

  1. Select the Windows 10 ISO and then click next
  2. Select the external drive that is listed in the drop-down menu
  3. Now select the EFI partition usually there will be a partition called EFI if everything goes fine
  4. Select the windows partition you want to install windows and click next
  5. Now be patient while windows gets installed and go back to your mac

Step 4: Final Steps

  1. Once the windows installation in complete plug the drive back into the mac
  2. Reboot ur mac and hold down the option or alt key on "Mac chime " on startup
  3. This is the mac boot menu select the 'EFI Boot ' option
  4. Now wait for windows to boot up
  5. Do not turn off or unplug the drive until u finish the start up steps and get to the windows desktop
  6. u will notice that everything in the desktop is very small(on retina diplays) this due to the high resolution
  7. Open the BootCamp folder and run the Setup app to install the Boot Camp drivers

    Thats it your done now u have an external drive with both bootable windows partiton and one avialable for mac(Mac can read both partitions but windows can only read the NTFS partition), u can use the mac partition as spare space to install apps or a time machine drive

Step 5: