If you are unable to see a shared mailbox account in your "From" field, follow the instructions below:
- Compose a new message in OWA (Office Web App).
- Click on your email address and press delete.
- Type or paste the email address you wish to Send As.
Note: You must have permission to send as this email address.
- Send your message.
Going forward, this email address should be listed in the drop down menu in your "From" box.