My Passport Ultra can’t save documents on Mac

Hi, I can open my files on my Mac computer but unable to save back to the hard drive.
I have installed the WD app onto my Mac computer.
I did first operated it on a PC where I transferred files onto the hard drive.
I’ve looked on the support and it says something about formatting the hard drive in exFAT or FAT32 but I’m not sure which one to use?
Can anyone help?


Sounds like your drive still formatted as NTFS, like the support site says, you might need to reformat the drive to make it fully compatible with the Mac. Please note that formatting the drive will erase all the information on the drive.

My recommendation is, to take the existing information out of passport and then reformat the drive using the exFAT option if you have a modern Mac.