WD 2TB My Passport for Mac Inquiry

Can I use this for both a Mojave Mac and a OSX El Capitain Mac? (I’ll be transferring the files between the two). I just bought one but will need to return it if not.

Hi,

You will be able to transfer data between the two if the drive is formatted in HFS+ or exFAT file format: Instructions to Format a Drive for Use with Windows or macOS