- Navigate to “portal.office365.com”
- Click “Admin” down the left hand side.
- Select “Users”
- Select “Active users”
- Select the desired user from the list
- Navigate to “Mail”
- Scroll down and click on “Manage automatic replies”
- Click the box to “Turn on automatic replies”
- Type your message in both boxes for inside your organisation and outside your organisation and click “Save changes”