Need occasional access to Windows on your Mac? Install it from a USB key …


If you need occasional access to Windows and don’t want to install it from a DVD, a how-to guide by Sam Power may have the perfect solution. It talks you through exactly how to create a Bootcamp-compatible USB key installer for either Windows 7 or 8 compatible.

A 4GB USB key is sufficient, and the complete process can be done in 20-40 minutes.

(Update: sorry for the confusion. You can’t install Bootcamp onto a USB Key yet. You’ll need Paralllels or VWMware for that.)

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  1. Hadi (@jawadhadi) - 9 years ago

    It is a guide that lets you install Windows on OS X via USB. You have to allocate sufficient space from your precious SSD. You can not install Windows on USB.

  2. Daniel Juul Simonsen - 9 years ago

    The guide doesn’t show you how to install windows on a usb key, but from a usb key… so you still sacrifice precious SSD space.

  3. alphabetize1 - 9 years ago

    Sweet! I’ve been wondering how I could do Bootcamp from an external drive without taking up space on my main drive. I’ve got a 64 GB flash drive that has read/write speeds of 200 MB/s, this might be really really useful.

  4. Terry Henderson - 9 years ago

    That’s All Well & Good, But I Can Tell You Boot Camp 5.1 Creates The Wrong Partition Type On My Haswell Core i7 Late 2013 iMac, It Makes A Guid When It Should Be A MBR , So The Install Fails, Every Time.

  5. Simon Brückner - 9 years ago

    As far as I can see, the linked guide only describes how to install FROM a USB drive to the internal HD, not ONTO a USB drive.

  6. bipedxing - 9 years ago

    The linked how-to guide shows how to modify OS X to allow creation of a bootable USB installer not a bootable, external USB installation. Normally Macs with built-in optical drive must use an install DVD. The process still requires you to install Windows on an internal drive partition. I think the title should be clarified to “install it from a USB key”.

    • Ben Lovejoy - 9 years ago

      I’ve clarified the wording – the benefit to my mind is you can more easily install it for the rare occasions you need it, so don’t have to retain it permanently.

      • I can’t seem to find a clarification here. Still says “… install it on a USB key” and the article still speaks about not sacrificing space on your SSD.

      • thejuanald - 9 years ago

        Maybe rare occasions if you are in the art industry. Try setting up a scientific laboratory or any sort of industrial plant using OS X and then come back. I use OS X very, very rarely on my Air. I’m in Windows 8.1 around 98% of the time, and have allocated the drive space accordingly.

      • Ben Lovejoy - 9 years ago

        Interesting that you see it worth having OS X for the other 2 percent – is that for things you can’t do in Windows, or do you simply prefer OS X?

      • thejuanald - 9 years ago

        A mix of both actually. I enjoy both operating systems, I tend to stay in Windows mostly, however.

  7. protojimmy - 9 years ago

    The instructions don’t actually install Window on the USB key, these just create a USB Windows Installer on a Mac.

    Following his instructions will still install Windows directly on the Mac after partitioning the drive.

  8. Editing the info.plist might render your BootCamp App useless as Apple seems to have signed the file.
    This link describes how you can codesign your Bootcamp App to make it work again:

    This did the trick for me.

  9. Any one know how to get Windows 7 installed on a mid 2013 haswell macbook air?
    Seems almost impossible has I’ve tried everything. Including changing the boot.wim file to load the USB 3 drivers but still a no go. :(

  10. Erde Gaja - 9 years ago

    …lost 2 hours for nothing. Now I see the changes of your first text-version :-(

  11. Scott (@ScooterComputer) - 9 years ago

    Hey Ben, why don’t you also throw an Apple Feedback link in there [], since this whole thing is a huge dick move by Apple to begin with? There is no reason why they FORCE customers with DVD drives to use actual DVDs, other than they want to make this process as painful as possible. Which is kinda contrary to their marketing bullshit…

  12. marrie1 - 9 years ago

    It would be nice if you could in fact install windows on to a usb key. I rarely use windows and if I do its only to reprogram my amateur radio or use firefox when safari fails to work with a site. I do not want to waste 20 gigs of my space to install windows and my software which I’ll only use every 3 or so months or so.

    Take care and be blessed.


Avatar for Ben Lovejoy Ben Lovejoy

Ben Lovejoy is a British technology writer and EU Editor for 9to5Mac. He’s known for his op-eds and diary pieces, exploring his experience of Apple products over time, for a more rounded review. He also writes fiction, with two technothriller novels, a couple of SF shorts and a rom-com!

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