I'd like to install Windows 7 on my MacBook Pro, but as the internal hard drive cable is not working, I'm using it with an external hard drive plugged in which OS X is installed on.

When I try to install Windows 7 it says that I have to have an internal hard drive to install it. So I'm just wondering if there is a way that can make my laptop think that the external hard drive is an internal so I could install Windows, or is there any other way to install Windows?

I don't want to install Windows in a Virtual Machine.

2 Answers 2


You should be able to do this with dd by setting Removable to False.

Unmount your disk, then run…

dd if=/dev/zero of=/dev/disk2 bs=1 count=1

Don't forget to replace disk2 with the actual disk identifier. This command will erase the contents of the disk. Untested, be careful, usual 'not responsible if stuff goes wrong' applies :)

  • I think the OP want's to do a dual partition on the external, as OSX is currently running on it.
    – wrossmck
    Dec 10, 2013 at 20:04
  • @RossMcKinley I simply answered "make my laptop think that the external hard drive is an internal" which is exactly what this should achieve :)
    – grg
    Dec 10, 2013 at 20:06
  • Oh sorry, I didn't realise that each partition will have it's own disk identifier.
    – wrossmck
    Dec 10, 2013 at 20:12

Using Mac OS X's built-in Boot Camp Assistant (in Applications, Utilities Folder) you can install Windows 7. After install, when you turn-on your Mac, hold the Option Key to Boot into Windows. This method runs the Operating System off it's own Partition of the internal Macintosh Hard Drive. When you boot into it, Windows will be Full-Screen, and "running natively."


An alternative is to Run Windows INSIDE Mac OS X using a Free program called "VirtualBox." This way, VirtualBox will be in your Dock on the OS X side. You will launch it, and run Windows 7 (or any Operating System) Virtually. Please note, this will be slower, and will need certain Drivers. There may be limited Functionality running Windows inside VirtualBox, instead of natively inside Boot Camp. And it lacks some of the Hardware Features available to a Native Operating System.

If there is a "problem" with your MacBookPro's Hard Drive, I would consider getting a NEW Solid-State Drive (of say, 128 GB). This can be purchased for around $100-$125. A few benefits: your Operating System and Programs will boot/launch Faster.

It may also be a good idea to move all of your Media to the External Hard Drive (noting that they will only be available when the External HD is plugged-in via USB. Go to iTunes and in Preferences tell iTunes to use the External Hard Drive for Storage.

Check your MacBookPro Model Number on Wikipedia (search MacBookPro). Make sure to Upgrade your RAM to Maximum Capacity. Then, Download whatever version of Mac OS X is the latest that machine will run. After Mac OS X Snow Leopard 10.6.8, the Mac App Store is Available. That means all versions of Mac OS X after 10.6.8 can be easily downloaded via the Mac App Store onto a New Hard Drive.

So, basically: 1. Purchase the latest version of Mac OS X your MacBookPro will run for $20 in the Mac App Store (let's say Mountain Lion, or Mavericks on Tuesday October 22nd) 2. Purchase an SSD (Solid-State Drive) for around $100 at 128 GB 3. Plug the SSD into the Mac's USB Port. 4. Go in Disk Utility. 5. install OS X onto the SSD using Mac OS Extended (Journaled) 6. Turn-off the MBP (afterwards) 7. Flip the MBP over and open the botttom. 8. install the New SSD that you just installed Mac OS X onto. 9. Turn-on the Computer. 10. Run Boot Camp. 11. install Windows 7 onto it's own Partition, using Disk Utility again. 12. After install, boot into Windows by holding the Option Key after hitting the Power Button to turn the Laptop on (hold it down for a few seconds). 13. Install all the Microsoft Updates and Drivers for your Printer and Peripheral Devices. 14. ReStart into Windows. 15. After all this is done, any time you turn-on your Computer, you choose which OS to boot into. You can even choose a Default in Mac System Preferences, System, StartUp Disk.

  • 4
    This answer is going to need a series edit to address the issue at hand as opposed to be a blog post. 1. The OP stated the internal drive connector is broken. Why all the fluff about putting an SSD inside as the OP looks to run externally. 2. We should take the OP at face value when they stated they don't want virtualization and want to get boot camp to run or know why it cannot.
    – bmike
    Oct 20, 2013 at 14:52
  • apple.stackexchange.com/users/5472/bmike I answered the question correctly and the Mod down-votes me? And sometimes you guys Edit my Answers. You can have your website. I am done! Get a life. Oct 20, 2013 at 15:50
  • 4
    Windows 7 will not allow itself to be installed to an external drive, without some extra steps (like a 3rd-party installer). Your answer didn't address that issue at all. Oct 20, 2013 at 16:24
  • 1
    See What kind of behavior is expected of users? specifically Re: "Do not use signature, taglines, or greetings" and "Avoid overt self-promotion". See also Why can people edit my posts? How does editing work?. This site is a wiki. People can, and will, edit your posts, especially when you are violating the established etiquette. When in Rome... Oct 20, 2013 at 18:23

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