Here’s a useful, detailed write-up on the — covering what it is, where to find it, how to manage it, and practical tips for troubleshooting. Understanding the Blocked Senders List in Outlook The Blocked Senders List is a feature in Microsoft Outlook (part of the Junk Email Filter ) that allows users to specify email addresses or domains whose messages should always be treated as junk and moved directly to the Junk Email folder. Where Is This List Stored? The location depends on how Outlook is configured: