GMAIL SMTP certificate problem

[Berkay]

Hello,

I've been using gmail as a client for my zimbra account (business e-mail address) without any problem for n.5 years.

however, starting last week, I have started to receive an error message when I try to send e-mails. (receiving them is still fine).

"Server returned error: "TLS Negotiation failed, the certificate doesn't match the host., code: 0"

Some resources informs that, Google won't accept self signed certificates starting from april 2020, so I need to use a certificate signed by a recognised CA.

Do you have any solution for this problem? How can I resume using gmail for sending emails?

Thank you in advance

[fs.schmidt]

Hello,

You can use Let's Encrypt which is free:

https://wiki.zimbra.com/wiki/Installing_a_LetsEncrypt_SSL_Certificate