The message was forwarded to the following address: External address: {ForwardedAddress} To stop mail forwarding, have the ...

The message was forwarded to the following address:

External address: {ForwardedAddress}

To stop mail forwarding, have the recipient follow these steps.
  1. On the Outlook on the web Options page, go to the Forwarding section, which is under Accounts.
  2. Choose Stop forwarding.
  3. Choose Save.

If they don't see Forwarding under Accounts, their mail is probably being forwarded due to an inbox rule. For information about changing inbox rules, see Inbox rules in Outlook.