WD My Passport Studio

I think you’re in the wrong forum.

This forum is for the My Passport WIRELESS drive.   I think you’d want the Portable Drives forum, here:   http://community.wd.com/t5/WD-Portable-Drives/bd-p/BoardExample2

But anyway, chances are if he was using Macbook, he had the drive formatted with Apple’s HFS+ filesystem, which is not PC compatible.

Seagate’s HFS4Win might work in this case.

The other option is to use NTFS software on the Mac, and move the data over via the Mac.   NTFS is native for Windows.