I had an Outlook.com alias (send on behalf of) that was added a long time ago (and removed, but the option remained to send on behalf of), but now I've just added the same email account as a send-and-receive account with POP3. Now I have a duplicate, one send-and-receive and one "on behalf of" — how do I remove the "on behalf of" address? It doesn't show up under my aliases.