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Open the Disk Utility app from your Utilities folder and select your Macintosh HD in the sidebar.ĭisk Utility lists the hard drive format at the top of the window, beneath the hard drive name. If your Mac is currently in Target Disk mode, press and hold the Power button until it turns off, then restart it. How to check the format of your Target Disk Mac Check your hard drive format in Disk Utility. If you can’t update that Mac to High Sierra or later, you should check which format the Mac you put into Target Disk mode is using. Open System Preferences and click on Software Update to check for new updates. The easiest solution for this is to update the Mac you want to transfer files to. Earlier software can’t read APFS so won’t recognize your Mac. If the Mac you want to boot in Target Disk mode is formatted as APFS, then you need to use a computer running macOS High Sierra or later to connect to it. Update macOS or reformat your Mac Apple releases new software updates all the time, make sure your Mac is up to date. Whatever the reason Target Disk mode isn’t working, you should be able to fix it with the simple troubleshooting steps below.
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It’s impossible for us to say exactly why Target Disk mode isn’t working on your Mac.
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