I have two accounts that are hosted by Gmail. One is my personal account with a gmail domain, the other is a work account with our company's domain.
When I send or reply to mail from my Mac using Apple's Mail.app, replies to those messages always go to my personal account.
I looked in the obvious places - Accounts and Preferences. The only thing that seemed related was under the Composing preference, which was set to "send new messages from account to selected mailbox", which I think is the right one.
Can anyone offer some insight?