Hello,

I'm using your Email Store/Forward service and like it a lot. However, I have this mail delivery issue when using TLS on my mailserver (Postfix 2.11.7).

I have a certificate for my domain (including the mailserver subdomain) signed by Let's Encrypt. When I set Postfix to use TLS, turn on SSL/TLS connection security in your web interface and save the settings, I get this error when your server tries to deliver messages:

SSL_accept:failed in SSLv3 read client certificate A
SSL_accept error from mail.dynu.com[63.141.230.148]: lost connection

I only get this error with your server however. I can relay emails from my other machines on LAN (TLS without authentication) or from SASL-authenticated (and TLS-enabled) clients from anywhere with this setup. When I disable TLS on my server and in your interface, emails are delivered without a problem.

After some searching I found this happens when server doesn't trust the certificate. Isn't Let's Encrypt among your trusted CAs? Or is it something else? I would really like to have this connection secure.

Thank you,
Petr Hejl

We have made some modifications on our end regarding the certificate issue. Could you please try and let us know if your certificate is being accepted by our servers?

Hello,

thank you so very much :-). Everything is now OK and works even for virtual domains hosted by my server.