The following instructions show you how to stop the auto forwarding rules in Outlook.
Select the File tab
In the Info section, click Manage Rules and Alerts
Select the Tools, then choose Rules and Alerts from the menu list
You will have the Rules and Alerts window in front of you.
You can choose to either disable the rule temporarily or completely delete it from the list.
Untick the check box next to the rule you no longer want to be active.
Highlight the rule by selecting it
Click the Delete tool from the buttons available