The flashing question mark is your Mac's way of indicating that you have a problem finding the bootable OS. Usually, your Mac will start the boot process more quickly that you will never poster the flashing question mark on the display. But, most of the time you may find your Mac displaying the question mark icon, probably for the less time before the startup process gets finished or it may appear stuck on the question mark.  If you find any issues with it, you can take help from the experts at MacBook Support Number.

During the period, the question mark is flashing; your Mac is verifying all available disks for an OS it can easily use. Most of the problem like your Mac does eventually find a disk it can use as the startup drive and finishes the boot process. You can shorten, eliminate the problem selecting and running a startup disk in System Preferences.

In the first step, you need to click the “System Preferences” icon in the Dock and then choose “System Preferences” from the Apple menu.

Now, you have to click the “Startup Disk preference” pane in the System section of the System Preferences.

Here, you will get a list of drives that are connected to your Mac and have OS X, macOS, or another bootable OS installed on them will get displayed.  

Further, you have to click on the padlock icon located in the bottom left corner and then you are required to provide your administrator's password.

Then you have to choose the one you want to use as your Startup Disk from the list of available drives. At last, restart your Mac for the change to take effect.

Still, you are facing trouble with your Mac, or your Mac flashing the question mark then it might be possible that your Mac has some serious issues. Chances are your selected startup drive is having issues, possibly disk errors that may be preventing the necessary startup data from properly loading.

For more information and help, feel free to contact our Apple MacBook Technical Support Number +1-877-708-3372 helpline. The number will help you to catch our technical support quickly without any delay. Our technical support providers are available 24/7 round the clock with best and advanced approach.

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