Formatting a drive always erases all of the data on the drive. If the USB drive that you want to use as a universal transfer drive contains any data that you want to keep, you’ll need to back up that data onto another disk or a cloud backup service first.
RELATED: Why Does Windows Want to Format My Mac Drives? Before You Get Started: Back Up the USB Drive First This disk preparation setup process is called “ formatting.”
Below, we’ll show you how to set up a USB drive as exFAT for both Windows and Mac. That file system is called exFAT, and it’s designed for flash media cross-platform compatibility. If you’re frequently using both Macs and PCs with the same drive, the ideal solution is to configure a USB drive with a file system that both operating systems can read. And likewise, if you format a USB drive as NTFS on Windows, Macs can read it but not write to it (although there are some ways around it). So here’s the problem: If you format a USB drive as APFS on a Mac, Windows 10 won’t read it without third-party tools (and will actually ask to format it).
