When you have multiple mailboxes in your Outlook profile, changes to "Rules" and "Out-Of-Office" replies only affect the primary account mailbox.  If you want to change the Out-Of-Office message for another mailbox, you must login as that mailbox.  This can be achieved by creating another profile.

  • Close Outlook by selecting File --> Exit
  • In Windows, click on Search --> Control Panel
  • Make sure you are Viewing by Small icons 
  • Click on the Mail icon
  • Click on the Show Profiles... button
  • You will see an existing list of profiles. Click on the Add... button
  • Type a profile name (usually the mailbox name that you want to connect to, but anything you want), click OK
  • Select Manual setup or additional server types and click Next
  • Select Office 365 and type the full email address of the mailbox, click Next
  • You should get check marks to show it was setup and connected successfully.  Add a check mark next to Change settings and click Next
  • Remove the check mark beside Use Cache Exchange Mode, and make sure there is NO check mark beside Set up Outloook Mobile on my phone, Too and click Finish
  • You should now see the new mailbox in the list of mailboxes.  Take note of what mailbox is listed under Always use this profile and then select instead prompt for a profile to be used
  • Click OK

Now when you start up Outlook, you will see a prompt asking you which mailbox you would like to open.  Most often, you probably want the default, so you can simply hit the Enter key on your keyboard to go into your regular profile.  When you want to see the other mailbox, simply select the name from the dropdown list and click OK.

When you are ready to go back to your original profile, exit Outlook from File --> Exit, wait 5 seconds and then restart Outlook and repeat the process.

If you get tired of the prompt to select a profile, or no longer need it:

  1. Close Outlook by selecting File --> Exit
  2. In Windows, click on Start --> Control Panel
  3. Make sure you are Viewing by "Small icons" and click on the Mail icon
  4. Click on the Show Profiles... button
  5. Select Always use this profile and then select the original default profile (usually called "Outlook")
  6. Click OK and start Outlook normally.