The Postmastery Blog: Insights, Tools & Best Practices for Email Deliverability
Check your emails with emailaudit.com
2010/01/01 by Maarten Oelering.
We recently launched a service to check your emails against standards, guidelines, and best practices. This service is called EmailAudit and is available on emailaudit.com. It checks DNS, SPF, headers, DKIM, DMARC, and more. The results are not a simple pass or fail, but contain detailed information on compliance and suggestions for fixing. EmailAudit was […]
PowerMTA Email Relay Solutions for Marketing
2010/01/01 by Maarten Oelering.
If you are a sender providing email relay services, how do you make sure that bounces and complaints are properly handled? Often the emails are generated by applications that hand-off the delivery to a relay service but have no means for processing returning bounces. This was also a question at 1-2-1 Marketing, a Texas based […]
Categories: Case Studies, General, PowerMTA
About the Return-Path header
2010/01/01 by Maarten Oelering.
The most common error senders make is adding a Return-Path header to their mail. Even some well known mail software does this. Probably written by programmers who copy from others rather than reading RFCs (the internet standards that specify SMTP and MIME). What does the standard say about Return-Path? The following fragment is from RFC […]
Categories: General
Interspire bounce processing add-on for PowerMTA
2010/01/01 by Maarten Oelering.
Interspire is perhaps the most popular email marketing tool. Used with PowerMTA, it becomes a powerful and complete email solution. But the two were not integrated with regard to bounce processing. Until now. Postmastery regularly set up turn-key email systems based on Interspire and PowerMTA. The systems were complemented by a POP/IMAP server so bounce […]
DKIM recipe for PowerMTA
2010/01/01 by Maarten Oelering.
DomainKeys, and it’s successor DKIM, are important email authentication techniques. Based on cryptography, they are more secure than SPF and Sender ID. With DomainKeys/DKIM the integrity of the content is also protected and authentication does not break when emails are being forwarded. DomainKeys/DKIM is used by large webmail providers such as Google, Yahoo and AOL. […]
Hotmail throttling and PowerMTA
2010/01/01 by Maarten Oelering.
Windows Live Hotmail is famous for throttling senders based on their IP reputation. The following two SMTP errors might be familiar: 421 PR(ct1) The mail server IP connecting to Windows Live Hotmail server has exceeded the connection limit allowed. If you are not an email/network admin please contact your E-mail/Internet Service Provider for help. For […]