So I have two accounts on my mail app, lets just call them 1 and 2. 1 is my main one, I've set everything to automatically send from that one. They're both gmail. If I do something like reply to a craigslist ad by clicking the email link (which is about 90% of my sent emails from my mail app), it'll send from account 1. When the person replies, it says that 1) I sent the original email from account 2, 2) the email back was sent to account 2, and 3) when I reply, it automatically sends from account 2. What do I do? It's extremely annoying, and I just end up using account 2 most of the time because I can't get it to work properly. Both accounts receive email fine, and 90% of the email that I get and don't reply to is to account 1.