I bought this as a back-up solution for the previous version Western Digital My Passport, which I have had no problems whatsoever with. This is a different story. It comes with some pre-installed tat called "SmartWare" - which causes any number of issues. I've tried various ways to format the drive to Mac, to no avail. It seems that the SmartWare programme is causing a conflict when creating a new partition, which makes the reformat impossible.
I've been on all kinds of forums as well as the WD technical support site to try and resolve this - and despite me clearly not being the first to experience the problem, there is no workable solution that I can find.
I'm sure there'll be a chin-stroking nerd reads this and thinks 'pfft' and knows some convoluted way of sorting it out, but at this stage I'm past caring. I use a Mac precisely so I don't have to get into things like partitioning drives, and the whole experience with this thing makes me want to throw the whole lot into the garden and go back to pen and paper.
Extremely frustrating considering how well the previous generation of WD My Passport worked, and indeed still works.
A dreadful, infuriating, time-wasting product.