No send registration email with SMTP

When I register I don't receive the registration email. I have no problems with joomla registration including mass mail, an CB registration using php-mail My Joomla Global configuration:

public $mailonline = '1';
public $mailer = 'smtp';
public $mailfrom = 'server@mydomain.com';
public $fromname = 'My web title';
public $sendmail = '/usr/sbin/sendmail';
public $smtpauth = '1';
public $smtpuser = 'server@mydomin.com';
public $smtppass = '*****';
public $smtphost = 'localhost';
public $smtpsecure = 'none';
public $smtpport = '25';


In debug I receive this error.

Warning: stream_socket_enable_crypto(): SSL operation failed with code 1. OpenSSL Error messages: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed in /var/www/vhosts/xxxxxxxxxxx.com/httpdocs/libraries/CBLib/CBPHPMailer/CBSMTP.php on line 371

I don't know what is the problem because my SMTP security is none (No SSL or TLS)

Could you help me please?

Have moved your topic out of single add-on support as it has nothing to do with the add-on you've purchased. Single add-on support is strictly for support for specific add-ons purchased.

The SSL certificate for your SMTP server does not match your domain name. Contact your host as the host name you supply in Joomla for SMTP needs to match the certificate.

Hi, I have Lets Encrypt on my server. I don't have an option to add a mail record like smtp.domain.com to the certificate. Normally I just send through SMTP either using localhost, or the server's default mail domain.

I have lots of components with various advanced mail settings and have never run into this issue before.

There must be another solution to avoid this error?

PHP 7.1.13
CB - updated today
J! latest
Using SMTP mail config in Joomla with authentication
HTTPS certificate, yes.

That error typically only happens when the SSL certificate is invalid (likely out of date) or there is a host mismatch (should be a different error I believe). The only fix is to contact your host and have them update their certificate and make sure your SMTP settings properly match the certificate. Anything working with an invalid certificate has specifically set verify_peer to false and is a security vulnerability. Joomla however falls back to phpmail if SMTP fails. Try using phpmail and see if issue persists.

I can't seem to get this right. Certificate is up to date. Domain/ host names match. I even receive the test mail from Joomla. Just the CB mails don't come through.

We do not want to use PHPMailer.

You are likely experiencing Opportunistic TLS functionality in the version of PHPMailer library we're using (specifically 5.2.22). This checks if the server is advertising TLS and if it is a secure connection is used. If the certificate is invalid this will fail. This means your mail server is saying "yes, use a secure connection, but our certificate isn't valid"; that's a security vulnerability and it's failing for good reason, which is that the connection is not secure. The server either needs to stop advertising TLS or provide a valid certificate.

It works for Joomla because Joomla specifically implemented a workaround for this feature introduced in PHPMailer 5.2.10.

github.com/joomla/joomla-cms/pull/9528

Have added a feature ticket to review updating our PHPMailer library to latest where this maybe better handled. There are no plans at this time to implement workarounds for, likely, incorrectly configured servers.

forge.joomlapolis.com/issues/6981