According to a Return Path’s latest Deliverability Benchmark Report, of the 21% of email that is not delivered to the inbox, only 3.3% is sent to a “junk mail” folder and 17.4% is not delivered at all – it just vanishes!

Return Path did not state where they believe the email to be, but we suspect that it is floating in deep space, possibly captured in the crystal prison of the three Krypton prisoners from Superman.

Some other notable points from the study:

• It is easier to deliver to US ISPs than Canadian ISPs. Inbox placements of mail sent to US ISPs was 82% in contrast to 75% sent to Canadian ISPs.
• B2B delivery rates are less than that of B2C email 72% vs 79%. This is in strong opposition to what has normally believed to be the case. Accounting for this is the fact that businesses are being protected by ever advancing systems like Postini, Synamtec and MessageLabs.
• In the US, Gmail is the hardest ISP to penetrate and Cox is the easiest.
• In Canada, Primus.ca was the hardest ISP to penetrate and Telus was the easiest.

I encourage you to download the full study, which is brief but very informative, and includes colorful charts and graphs:

Return Path Deliverability Benchmark Report

We built an auto-responder that can be used to test your bounce and feedback loop processing systems. Feel free to use it for your testing purposes.

fbl-test@service.socketlabs.com
Auto responds to From address with a feedback loop report in ARF format.

bounce-test@service.socketlabs.com
Auto responds to the Return-Path with a bounce message.

As a side note, the autoresponder was built using the .Net API in Hurricane MTA Server.

We just released a new production release of Hurricane MTA Server and there are two things you should know about it:

First, now our new Dynamic Block Rules are a part of the Smart Delivery Rules. Now, protecting your reputation is automatic. You can read more about Dynamic Block Rules here.

Second, Smart Delivery Rules can now be updated easily from within the Hurricane MTA Server interface without having to update the entire application.

The Administrative configuration page has a new option to download and apply the latest set of Smart Delivery Rules directly from our database.

With these two enhancements it is now easier than ever to leave things up to us and still be assured of the highest deliverability possible. Enjoy!