Once you have backed up all your data, you can try a few fixes to your “unmountable” hard drive problems.Ĥ Fixes to a MacBook Pro That Can’t Mount Its Startup Disk You can now start backing up your data using the external drive.Choose Disk Utility and hit Continue to proceed.The macOS Utilities window will now appear.After hearing the startup sound, press the CMD and R keys.Get an external hard drive and connect it to your Mac.About Outbyte, uninstall instructions, EULA, Privacy Policy. Here’s what you should know: your Mac has a built-in Disk Utility, which can be accessed before startup. Now, you might be wondering if it is possible to create a backup of your data, especially that your Mac is not even booting. That way, you can easily retrieve or recover your important documents and files in case something goes wrong. Backup, Backup, Backup!īefore you proceed with fixing the problem, it is best that you back up all your data first.

But before we do that, you better have a backup of all your data. Situations like this can be very annoying, especially if you have critical and important files stored on the “unmountable” hard drive.įret not, because we will teach you what to do if your MacBook Pro won’t mount its startup disk. That means if your Mac or MacBook Pro can’t mount its startup disk, it is likely that you will experience problems, like your computer gets stuck on the login screen or it does not boot at all. Macintosh HD, or the MacBook internal hard drive, is basically the startup drive of most Apple computers.

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