2018/06/11 by Olivier.
Postmastery assists various senders every day with delivery monitoring tools and consultancy services. In order to assist the global email senders community, we are happy to share some ISP specific information we collected over the last few years. This blog post looks at some more details, this time related to Orange.fr. Orange: the biggest French ESP […]
2018/04/10 by Willem.
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 […]
2018/04/06 by Willem.
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. 451 4.7.650 The mail server [xxx.xxx.xxx.xxx] has been temporarily rate limited due […]