We are having a problem with Mac Mail and was wondering if anyone could help. Our inbox has six different accounts, but whenever we answer an email or start a new message it will always be sent from the same email address and we can't seem to change it which is causing a lot of issues. We have tried changing the default, searched forums and none of the solutions will work. This is the main forum we found (https://forums.macrumors.com/threads/1371261/) but after following the suggested solution it still won't work and nothing has been solved. We are using Mail version 5.3. Can anyone help?