I bountied this question Boot into Mac from Windows after failed Bootcamp after being trapped in Windows hell on my mac, after the first time using boot camp.

When I got back to my mac I erased windows and reformatted boot camp following the answer to this question How to remove Windows Operating system from Bootcamp?

If you installed Windows on a disk that has a single partition

  1. Start up your Mac in OS X.
  2. Open Disk Utility, located in the Other folder in Launchpad.
  3. Select the Windows disk, click Erase, choose the Mac OS Extended (Journaled) >format, then click the Erase button.

Now whenever I restart my mac I have to hold onto the option key to select the mac (and reboot it from there as it defaults to the Windows keyboard and the keys do not match, so I cannot submit my password - don't' ask).

This is what I have when I open boot camp and disk utility:

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Erasing the boot camp volume does nothing, as does unmounting. I'm too scared to play around with it beyond this. If I never had to touch Windows OS again I'd be happy, but it's an unfortunate evil. I've gone back to Parallels desktop.

Most of the solutions I've found online have not helped me remedy any of these issues from trying to make it work to wanting to get rid of it - which is why I'm here.

I accept I may have sacrificed the disk space and may never be able to claim it (grrr can't think too hard about it). But I swear to Apple, they'll be taking this machine back if I can't stop it from booting up on Windows.

My machine:
iMac (Retina 5K, 27-inch, Late 2015)
4 GHz Intel Core i7
32 GB 1867 MHz DDR3

How can I stop my mac from defaulting to open Windows?

  • Great linking and use of a bounty. I see the erase procedure as potentially a new question thread. Asking bootcamp to remove a partition is fragile and can break. You’re always safe to make a good time machine backup and then erase / install - repartitioning the drive itself as GUID and one volume. support.apple.com/en-us/HT204904 - hopefully NVRAM and a new election in startup pref pane works for you.
    – bmike
    Sep 9, 2018 at 20:50

1 Answer 1


The NVRAM holds the location of the default OS, so resetting that might get you back to the default search order. If you want to set it explicitly, Apple’s article linked below as well can help:

From How to select a different startup disk:

Use Startup Disk preferences

When you use Startup Disk preferences to select a startup disk, your Mac starts up from that disk until you choose a different one.

  1. Choose Apple () menu > System Preferences, then click Startup Disk.
  2. Click the lock and enter your administrator password.
  3. Select your startup disk, then restart your Mac.

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NOTE: Restart the Mac by clicking the Restart... button. This process checks the system has the correct permissions to start, then writes your choice to NVRAM.

  • Yep and I tested it - a random restart and it's working. You will note, I only have one start up option, even though it was starting in bootcamp - uninstalled windows
    – user301529
    Sep 9, 2018 at 20:23
  • @bmike, yeh the addition of NVRAM makes sense. It's driven me nuts.
    – user301529
    Sep 9, 2018 at 20:25
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    I urge you to expose Apple url as plain text - add the English title after if you want that too. People on iOS can’t see you are linking to an official Apple KB article as you have written it
    – bmike
    Sep 9, 2018 at 20:37
  • @bmike, you said, "People on iOS can’t see you are linking to an official Apple KB article as you have written it", well while I have not used iOS for a while nonetheless, unless things have changed, one can tap and hold the link to see a Link URL preview which one can take action on. As to "I urge you to expose Apple url as plain text", you and I have never seen eye to eye on this subject and while I have respected your wish to not edit your posts with raw URLs, please show me that same respect. Thanks! Sep 9, 2018 at 20:52
  • I didn’t roll back your change and simply explained in comments why I made the change - I totally understand you’ve thought about this as well - your edit was just fine by me. We (the larger community) can discuss in Ask Different Meta whether we want to formalize any preference. Tapping and holding causes all sorts of pain on iOS and is super inferior to just letting the text show clearly but you are right, there isn’t a community consensus today.
    – bmike
    Sep 9, 2018 at 20:55

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