- Click on the File tab at the top-left corner of the window.
- Then, click the Account Settings button, followed by "Account Settings" in the dropdown menu.You should see a list of your email accounts.
- Click on the one you want to edit, then click "Change."
- In the Change Account window, click on "More Settings."
- In the Internet E-mail Settings window, under the General tab, there should be a field where you can enter your Reply Email. Once you change it, click OK, then Next, then Finish, then Close.
There currently is not a way to change the reply address on an Exchange account.