Eliminate Unknown User Errors
ISPs block domains in part based on the number of "unknown user " errors generated when sending mass e-mails. Keeping your e-mail list clean and current will help lower the percentage of bad addresses on your list resulting in "unknown user " codes at ISPs. Some things you should do:
* Use a bounce algorithm that will remove all bad addresses from your file promptly, handing both "inline" and "message" bounces.
* Process your file through a consumer-reported e-mail change-of-address service.
* Run your file through a list hygiene service.
* Require double entry of addresses for accuracy.
* Check addresses for RFC compliance and ISP standards.
* Send a welcome message and pull bounces off immediately.
—Back to the Basics: Deliverability 101 - Getting your email into the Inbox,"
a free white paper by George Bilbrey, VP and GM of Deliverability Solutions,
Return Path. To download a copy, visit www.returnpath.com