Which Mac Mail account supplies the "from" email address with Send Mail?
Not having a Mac to test and research this on, I can't fully answer my client's question:
He has more than one email account set up in his Mac Mail client. He can't find a way to determine which of his accounts supplies the "From" email address when he uses Send Mail to send out an email.
He was thinking that the "first mail listed in his account" would supply the email address, but has discovered that this is not the case.