Microsoft uses these submissions to improve the effectiveness of email protection technologies. The Report Message add-in for Outlook and Outlook on the web (formerly known as Outlook Web App) enables people to easily report false positives (good email marked as bad) or false negatives (bad email allowed) to Microsoft and its affiliates for analysis. If emails continue getting sent to your spam even after you add the email address to your contacts, you can completely override the spam filter with the “Safe Senders” list.

While Outlook.com will prioritize emails from your contacts, it may still send them to spam if they look unusually spammy.