I activated my Mail account yesterday and thought it was great until I saw that it used up 3 GB of my hard drive space after I had done this. I'm assuming it's due to importing all my emails and attachments from my Gmail account. How can I undo all of this safely and get my Mac and my memory space back to what it was before I activated this yesterday? I'd rather not use mail now that I see it is storing everything on my hard drive and taking up so much space.