Hello! Could it be that Courier MTA cannot be configured to send emails securely (using SSL) to Sendgrid because they have their hostname in SAN not in CN?
Thanks. ----- Forwarded message from "James (SendGrid Support)" <[email protected]> ----- Date: Thu, 16 Feb 2017 22:38:40 +0000 From: "James (SendGrid Support)" <[email protected]> ## In replies all text above this line is added to the ticket ## James, Feb 16, 15:38 MST I brought this up to our securities team and they relayed this info to me: Our certificate for smtp.sendgrid.net has a common name (CN) of: ``` Subject: OU=Domain Control Validated, CN=*.smtp.sendgrid.net ``` however, we also have a Subject Alternative Name (SAN) of: ``` X509v3 Subject Alternative Name: DNS:*.smtp.sendgrid.net, DNS:smtp.sendgrid.net ``` so our certificate is technically valid for smtp.sendgrid.net, but the client has to check it according to [Subject Alternative Name](https://en.wikipedia.org/wiki/Subject_Alternative_Name) rules. As for the configuration change, I am not familiar with Courier MTA and I am unsure as to why you're unable to send mail through SendGrid with those settings. It may be best to try reaching out to their support team for more assistance getting that set up (everything looks correct from what I can tell checking out their documentation), or have you already tried that? I look forward to your reply! James | Sr. Support Engineer</p> -------------------------------- This email is a service from SendGrid. ----- End forwarded message ----- SZÉPE Viktor https://github.com/szepeviktor/debian-server-tools/blob/master/CV.md -- +36-20-4242498 [email protected] skype: szepe.viktor Budapest, III. kerület ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ courier-users mailing list [email protected] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
