Problem
You have been granted access to send emails on behalf of another person or group, but new emails default to originating from your mailbox and address.
Environment
For all Microsoft Outlook - Mac, Windows, O365
Resolution
Adding an alternate sending address to Outlook - Changing the From: field
a. Open a new message
b. Select options at the top of the new message, then select "From" in the menu bar
- In Outlook 365, click the three horizontal dots at the bottom of a new message for options, then choose Show From in the menu that opens.
c. The From field in the message will change to a button/drop down, click it.
d. Select Other email Address
e. Enter the email address the user will be sending as & click OK
NOTE: The user must have read/send as permissions to the mailbox or distribution list.
Cause
By default, Outlook will send messages from your primary mailbox with your own email address. But if you have been granted access to another person's mailbox, or a group, there may be times you wish to send an email from that address, rather than your own.