Option Key on Start-up Not Working


I’m trying to do a clean install upgrade to Sierra on my 2010 MacPro. I’ve downloaded the installer to USB drive, and just trying to access Startup Manager via an Option key startup to start up in the installer.

Each attempt only delivers a blank screen, no startup manager.

I have tried:
Resetting PRAM and SMC
Tried both a Bluetooth and wired keyboard (same blank screen result).
I’ve tried multiple times with different key press timing.

The fact that it is not starting up correctly means it’s recognising the key press, but it’s just not going to startup manager.

Normal startup resumes if I press no key.

Any Ideas?


You could try booting the mac up normally and mounting the USB key, then setting it up as your Startup Disk, using the pref pane in System Preferences of the same name.


It is most likely that the particular USB stick that you are usiong is not 100% compatible with the Mac, I’ve had this happen myself. As a workaround try booting up hold down command+option+R to boot into recovery mode and do an Internet based recovery.


The problem with Internet Recovery is that it restores the original macOS that was supplied with the Mac…


They changed Internet Recovery recently, so now it behaves slightly differently depending on which key combo you use: https://support.apple.com/en-au/HT204904

Have you tried getting to startup manager without any USB key plugged in? Even without anything plugged in, holding down option at boot should still give you the option to boot from your primary boot drive.


Yes I thought of that but it doesn’t show as a startup disk option (despite me testing and confirming I could run the installer from the USB). It could be as Acelon1 has suggested there is some issue with the USB drive - and it is true that it has been plugged in each time I’ve tried to Option key startup.

I’ll try without the USB (at work away from my mac at present).

Thanks folks.


Thanks Benny that’s the link I was trying to find to post along with the information I did.


Righto, I tried option-start up with the USB drive not plugged in, and same result, blank screen. I still can’t access startup manager.

Of course all I want to do is do a clean install upgrade, why can’t I do that was the installer, Apple??

If there any other way I can do a clean install upgrade without being able to access the startup manage?


Definitely a couple of different ways, one of which is the second post:


Yes I thought of that, but despite the Mac seemingly letting me run the installer from the USB and upgrade my startup disk if I wish (I tested it, it will), when I go into Preferences the USB does NOT show as a startup disk option, go figure!

None of this still answers my original question of why I cant option key startup, its very irritating Mac bug.


Wait… did you use the USB installation media creation tool, or did you just drag the installer onto the USB?


Umm, dragged it to the USB key…is that were I have gone wrong?


What OS are you installing? You need to run a command in Terminal to properly format the USB drive and copy the installer.

The commands are below. Before running them you need to rename the USB stick you want to use to “INSTALL” (without quotes). This command will format the USB stick so don’t leave anything else on it! :slight_smile:

Importantly, in my experience, the Install macOS Sierra app needs to be in the Applications folder for this to work (you can’t just substitute the path). I had trouble running the command when the installer was on another volume, for example.

So, insert USB key named “INSTALL”, make sure the OS installer app is in Applications, and then open terminal and run:

For a 10.11 installer

    sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/INSTALL --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app --nointeraction

For a 10.12 installer

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ macOS\ Sierra.app

Enter your user login password when requested, wait and you’re all done. :slight_smile:

It’s all covered here: https://support.apple.com/en-us/HT201372