Thanks for reading this. I appreciate anyone's thoughts. I'll be as brief as I can. I am using a MacBook Air, and the most current version of Mail. I tether internet to my MacBook Air via Mywi. Mywi shows you how much downloading/uploading you are doing. (My issue is not a Mywi issue; just a Mail issue.) Earlier, I opened Mail and attempted to send an email. Admittedly, the email contained one large photograph, high resolution. When I saw that that it was taking a long time to send the email, I attempted to stop it. I turned off Mail, and then back on. I found the email in the "outbox," and deleted it. But something - either that original email, or something else entirely - won't stop trying to go out; here's what I mean. First, Mail is currently trying to send some sort of email - showing the progress in the lower left-hand corner. Second - and here's the problem - whatever the email is, it is MASSIVE; the Mywi indicator shows that it has sent 175 megabytes in the past hour, and the Mail progress bar in the lower left corner confirms that whatever it is trying to send is creeping out of Mail due to its large size. Third - strangely - the original email that contained the picture - the one I tried to stop - has already made it to its destination. I know this because the person responded to me. I am concerned for third reasons. First, I don't want this massive increasing in uploading to flag AT&T. Second, I don't know what is actually being sent; anything that is 175 megabytes big - at the halfway point - could be something else entirely, something confidential. I just don't know. I just want to find it and stop it. Third, Mail is not sending or receiving any other email while it's attempting to send this mystery email out. So, in short, the only way I've found to stop this process is to close Mail out. The moment I open it again, though, it resumes trying to send this. How do I find and stop this mystery outgoing email? Thanks for your time.