I made a mistake.... how can I fix this?

So I didn’t realize there were seperate mac and pc externals. I just got the 3TB My Book and I couldn’t get it to work.
Now I’m looking on here and see there is a mac version.

What can I do now?

Ok, I finally got it working with journaling mode. Wish I knew what that meant… oh well

Hi RyanDC, as you already figured Windows formatted drives can also be formatted for Mac. Check the link below for more info on file system journaling. 

Mac OS X: About file system journaling