There was a problem while sending the test email.

Replies: 0

Hello,

Yes, there’s already a topic about this, but it didn’t help me solve my problem :/

I tested the credentials using smtper.net and it works fine.

I also added:
define( 'WPMS_ON', true );
define( 'WPMS_SMTP_PASS', 'password' );

In the wp-config file, it didn’t help :/

So I hope this will help:

Versions:
WordPress: 4.9.8
WordPress MS: No
PHP: 7.2.10-0ubuntu0.18.04.1
WP Mail SMTP: 1.3.3

Params:
Mailer: smtp
Constants: Yes
ErrorInfo: SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
Host: domain.xyz
Port: 25
SMTPSecure: string(0) “”
SMTPAutoTLS: bool(false)
SMTPAuth: bool(true)

Server:
OpenSSL: Yes
Apache.mod_security: No
SMTP Debug:
2018-11-29 01:49:13 Connection: opening to domain.xyz:25, timeout=300, options=array (
)
2018-11-29 01:51:23 Connection: opened
2018-11-29 01:51:23 SERVER -> CLIENT: 220 domain.xyz ESMTP Postal/AQY3TM
2018-11-29 01:51:23 CLIENT -> SERVER: EHLO domain.app
2018-11-29 01:51:24 SERVER -> CLIENT: 250-My capabilities are
250 AUTH CRAM-MD5 PLAIN LOGIN
2018-11-29 01:51:24 CLIENT -> SERVER: AUTH CRAM-MD5
2018-11-29 01:51:24 SERVER -> CLIENT: 334 PDRmNmE4NDYwMjI0OThiNWY4MTVkQGJrbWxyLnh5ej4=
2018-11-29 01:51:24 CLIENT -> SERVER: YmttbHIva21scmFwcCA3ZWNmOTI2NDQyOWU2MzgwMjIxNGUxY2UxODJiMWNmYQ==
2018-11-29 01:51:24 SERVER -> CLIENT: 535 Denied
2018-11-29 01:51:24 SMTP ERROR: Username command failed: 535 Denied
2018-11-29 01:51:24 SMTP Error: Could not authenticate.
2018-11-29 01:51:24 CLIENT -> SERVER: QUIT
2018-11-29 01:51:24 SERVER -> CLIENT: 221 Closing Connection
2018-11-29 01:51:24 Connection: closed
2018-11-29 01:51:24 SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting