--- title: Are You Receiving Replies to Messages you Never Sent? description: Backscatter Protection works by adding a special key to the return-path of all outbound mail to recognize a legitimate bounce-back message. image: https://blog.mdaemon.com/hubfs/Return-to-Sender.png --- [![MDaemon Technologies](https://blog.mdaemon.com/hs-fs/hubfs/MDaemon-Technologies_logo_large.png?width=564&height=110&name=MDaemon-Technologies_logo_large.png "MDaemon Technologies")](https://mdaemon.com/) - [Blog Home](https://blog.mdaemon.com) # MDaemon Technologies Blog ## [Are You Receiving Replies to Messages you Never Sent?](https://blog.mdaemon.com/are-you-receiving-replies-to-messages-you-never-sent) By [Brad Wyro](https://blog.mdaemon.com/author/brad-wyro) - [Tweet](https://twitter.com/share) ![Return-to-Sender](https://blog.mdaemon.com/hs-fs/hubfs/Return-to-Sender.png?width=2240&height=1260&name=Return-to-Sender.png) Have you ever logged into your email to find tons of bounce-back messages (out-of-office replies, NDR messages, invalid recipient messages) in response to messages you never sent? For many users, their first thought is that they need to change their email password. However, changing your email password will not prevent this. Why? Because what you are receiving is known as backscatter, and has nothing to do with your email account being hacked.   Spammers often forge the return-path in their outbound messages to cover up their true identity. If the forged address in these spam messages was your address, then you are likely to receive the bounce-back messages and auto-responders in response to these messages.   So how do you prevent this? MDaemon includes Backscatter Protection. Backscatter Protection works by adding a special key to the return-path of all outbound mail. When MDaemon receives an out-of-office reply or non-delivery message, it looks for that special key. If the key is missing, then we know the bounce-back message is not legitimate and can be discarded.   When Backscatter Protection is disabled, the return-path of a message looks like this: X-Return-Path: frank.thomas@example.com   When Backscatter Protection is enabled, an extra series of characters beginning with prvs= is added to the return path - like this: X-Return-Path: prvs=163898ff65=frank.thomas@example.com   It is this extra series of characters that the Backscatter Protection feature looks for in bounce-back messages.   Check out the following video to learn more about Backscatter Protection and how to enable it in MDaemon. If you have questions, please feel free to leave us a comment & let us know! Tags: [Email Gateway How-To](https://blog.mdaemon.com/topic/email-gateway-how-to), [Email How To](https://blog.mdaemon.com/topic/email-how-to), [Email Security](https://blog.mdaemon.com/topic/email-security), [Cybersecurity](https://blog.mdaemon.com/topic/cybersecurity), [MDaemon Email Server](https://blog.mdaemon.com/topic/mdaemon-email-server), [Stop Spam Email](https://blog.mdaemon.com/topic/stop-spam-email), [Email Server](https://blog.mdaemon.com/topic/email-server), [Email Security Trends](https://blog.mdaemon.com/topic/email-security-trends) ![Brad Wyro](https://blog.mdaemon.com/hs-fs/hubfs/Brad-2023v2.jpg?width=100&height=100&name=Brad-2023v2.jpg) #### Written by [Brad Wyro](https://blog.mdaemon.com/author/brad-wyro) Brad has worked in technical and marketing roles at MDaemon Technologies, where he contributes as Content Marketing Manager. Brad balances technical and creative information to develop easy to understand videos and content to educate prospects and customers. 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[Windows Server (1)](https://blog.mdaemon.com/tag/windows-server) - [internal email threat (1)](https://blog.mdaemon.com/tag/internal-email-threat) - [ssl (1)](https://blog.mdaemon.com/tag/ssl) - [tax scams (1)](https://blog.mdaemon.com/tag/tax-scams) See all #### About MDaemon Technologies MDaemon Technologies is a pioneer in developing email and email security software helping to protect customers from evolving cyber-security threats. Its products and services are trusted by thousands of organizations in over 140 countries. For more than two decades, the company’s products have been developed with the ongoing input of IT professionals who demand reliable, affordable software that requires minimal effort to manage. The software can be deployed in virtual, hosted cloud, on-premises, or hybrid network environments. The company sells its software and services directly and through a network of global channel partners. For more information, visit [www.mdaemon.com](https://www.altn.com/). Copyright © 1996-2026 MDaemon Technologies.  View [privacy policy](https://mdaemon.com/policies/privacy-policy).   ###### Contact Us +1.817-601-3222 [sales@help.mdaemon.com](mailto:sales@help.mdaemon.com) 6340 Lake Worth Blvd. Fort Worth, TX 76135 ```json { "@context" : "https://schema.org", "@type" : "BlogPosting", "author" : { "@type" : "Person", "name" : "Brad Wyro", "url" : "https://blog.mdaemon.com/author/brad-wyro" }, "dateModified" : "2026-01-29T21:29:40.134Z", "datePublished" : "2015-07-15T19:19:36.000Z", "headline" : "Are You Receiving Replies to Messages you Never Sent?", "image" : [ "https://blog.mdaemon.com/hubfs/Return-to-Sender.png" ], "mainEntityOfPage" : { "@id" : "https://blog.mdaemon.com/are-you-receiving-replies-to-messages-you-never-sent", "@type" : "WebPage" }, "publisher" : { "@type" : "Organization", "logo" : { "@type" : "ImageObject", "url" : "https://blog.mdaemon.com/hubfs/MDaemon-Technologies_logo_large.png" }, "name" : "MDaemon Technologies" } } ```