Elliot Cater
Customer
- Joined
- Aug 29, 2017
- Messages
- 20
- Reaction score
- 4
Since upgrading to SP6 I'm having trouble with connecting to my Postfix SMTP server in the email settings.
My Postfix server is hosted on the same subnet as 3CX and is set to only allow SSL/TLS. I use letsencrypt for SSL and the certificates are verified as valid.
This SMTP server is functioning correctly for approximately 100 users with varying email clients (Thunderbird, iOS, Apple Mail, Android etc...) but for some reason the MailKit based client 3cx uses gives me this error message when I hit the TEST button:
As I mentioned before, the SMTP server's certificates are definitely valid (1&3 from the error message), Postfix is configured correctly and there is no firewall/content filter etc causing trouble between the 3cx or the Postfix server (both running Debian).
I've tried updating the CA/Root certificates on 3cx's Debian using update-ca-certificates (2).
My reseller is completely stumped and now so am I. I even installed a fresh Postfix instance onto the 3cx server itself and that did the same thing.
Is there some log files I can look at that might shed some light?
Thanks
My Postfix server is hosted on the same subnet as 3CX and is set to only allow SSL/TLS. I use letsencrypt for SSL and the certificates are verified as valid.
This SMTP server is functioning correctly for approximately 100 users with varying email clients (Thunderbird, iOS, Apple Mail, Android etc...) but for some reason the MailKit based client 3cx uses gives me this error message when I hit the TEST button:
An error occurred while attempting to establish an SSL or TLS connection. The SSL certificate presented by the server is not trusted by the system for one or more of the following reasons: 1. The server is using a self-signed certificate which cannot be verified. 2. The local system is missing a Root or Intermediate certificate needed to verify the server's certificate. 3. The certificate presented by the server is expired or invalid. See https://github.com/jstedfast/MailKit/blob/master/FAQ.md#InvalidSslCertificate for possible solutions.
As I mentioned before, the SMTP server's certificates are definitely valid (1&3 from the error message), Postfix is configured correctly and there is no firewall/content filter etc causing trouble between the 3cx or the Postfix server (both running Debian).
I've tried updating the CA/Root certificates on 3cx's Debian using update-ca-certificates (2).
My reseller is completely stumped and now so am I. I even installed a fresh Postfix instance onto the 3cx server itself and that did the same thing.
Is there some log files I can look at that might shed some light?
Thanks