Default sender in Apple Mail when replying and more than one account Using Mavericks Apple Mail, I have two Exchange mail accounts, one for myself and one for Jane Doe.  The accounts are organised in the left hand mailbox list with mine above Jane Doe's.  If I reply to mail sent to both myself and Jane Doe, the default Sender that Apple Mail uses (unless I change it with the pulldown menu of email addresses) is Jane Doe, but it should be myself (since I am writing the email).  Is this a bug, or behaviour that I can change?  Note that on Preferences > Composing I have set "Send new messages from:" to my email, but this doesn't make a difference (and indeed the setting says it is for new messages, while I am concerned with the Sender of replies.)
Lets differentiate between NEW massages send from and Reply to sender.

There are 2 settings in Mail for each of the purpose.


One is for new mails:


That is the setting to either use a specific account or current Mail box account.


The other is for Replay-To.


The Reply-To settings are in each individual account settings, there you choose which account is to be used in Replay-To.


Preferences- Accounts - Outgoing mail Server (SMTP)
set the Server there and check the box use only this server.


Make sure you use (set) different server setting there for each account.