2019/04/05 by Liselotte Rooseboom.
Meet Postmastery at various events and summits!
CSA Summit 2019 (April 10 – 12) Postmastery sponsors CSA, and we are pleased to again attend the CSA Summit 2019 in Cologne. CSA and Postmastery share a common objective: reliable and safe email delivery. CSA enables this by providing a whitelist and related legal and compliancy services. At Postmastery, we enable this common objective […]
Categories: General
2018/11/27 by Willem Stam.
Proper MIME prevents DKIM failures in Outlook
At Postmastery, we work for various ESPs and brands to optimise email delivery. Recently, one of our clients faced a mysterious DKIM failure when sending mail to Outlook.com domains. (A generic explanation of what DKIM is and how it works is available on dkim.org.) Analysing SMTP headers First thing we did was to analyse the client’s […]
Categories: Authentication, General
2018/11/01 by Liselotte Rooseboom.
Webinar PMTA insights
The Future of PowerMTA with Postmastery & Port25. Watch our joint PMTA webinar. On Tuesday 6 November, Postmastery and Port25 held a joint PMTA webinar. The PMTA webinar was a great success. Three panellists took part in an open conversation about the future of PowerMTA and the next steps. They answered questions from the PowerMTA […]
2018/08/31 by Liselotte Rooseboom.
Meet your deliverability peers at the Port25 summit, 20 September 2018, Amsterdam
This year too, Postmastery is the Premier Platinum Sponsor of the Port25 Summit. As co-organiser Postmastery’s complete team will be there to meet you. The Port25 Summit will be a highly interactive event. It brings together industry representatives, email deliverability experts, technology vendors, and senior email professionals to explore and discuss the trends that will […]
2018/07/11 by Willem Stam.
Postmastery supports SendGrid clients with multiple webhook endpoints
Postmastery provides delivery monitoring and optimisation services on top of various email delivery environments. Sometimes we offer this service on top of on-premises MTA (like PowerMTA or EmailSuccess) and sometimes on top of cloud-based ESP’s (like Mailchimp or Smartfocus). A prerequisite of delivery monitoring and optimization services, is to get the right data points like […]
Categories: Authentication, General, Sendgrid, Solutions
2018/04/10 by Willem Stam.
Delivery issues at LaPoste.net resolved
On Friday April 6, 2018, Postmastery’s Email Delivery Analytics detected serious delivery issues at LaPoste.net. The most frequent SMTP errors we detected were: 421 4.3.2 No system resources 421 4.3.2 All server ports are busy 451 4.7.1 Service unavailable – try again later 421 4.7.0 lpn-prd-vrin0xx Error: too many errors 421 4.4.2 lpn-prd-vrin0xx Error: timeout […]
Categories: Deliverability, General, Providers
2018/04/06 by Willem Stam.
New SMTP replies at Outlook: update your backoff patterns to avoid reputation damage
On April 5th, at 5AM CET, we were alerted by a huge spike in Outlook deferrals. The chart below (copied from Postmastery Delivery Analytics) reveals the deferrals over time: After investigating the issue, Postmastery delivery engineers discovered new SMTP replies at Microsoft domains. These errors are receiver’s side, not related to sender’s reputation. Organization queue quota […]
Categories: Authentication, Deliverability, General, Providers