The instructions below are for Windows 10, but other versions of Windows from Windows 7 and up can also format an external drive as exFAT for use with Mac as well. Connect the drive to your. You can format your external hard drive from either the PC or Mac. https://high-powerbrand.weebly.com/best-malware-app-for-mac-os-sierra.html. Just keep in mind if you want to use your drive also for OS X’s Time Machine backups, we advise you to format your drive through Mac because there is an additional step to make drive compatible with “Time Machine Backups”. If you’ve just purchased a new external hard drive for your Mac, it’s important to take the time to prepare your hard drive for use with Mac OS X. Like a lot of operating systems, Mac OS X offers only limited support for other file systems.