2020-05-31 03:03:49 CLIENT -> SERVER: EHLO portalcucicba.com.ar 2020-05-31 03:03:49 CLIENT -> SERVER: STARTTLS 2020-05-31 03:03:49 CLIENT -> SERVER: EHLO portalcucicba.com.ar 2020-05-31 03:03:49 CLIENT -> SERVER: AUTH LOGIN 2020-05-31 03:03:49 CLIENT -> SERVER: bWlnQHBvcnRhbGN1Y2ljYmEuY29tLmFy 2020-05-31 03:03:49 CLIENT -> SERVER: MTIzbmlhZ2E= 2020-05-31 03:03:51 SMTP ERROR: Password command failed: 535 5.7.8 Error: authentication failed: UGFzc3dvcmQ6 2020-05-31 03:03:51 SMTP Error: Could not authenticate. 2020-05-31 03:03:51 CLIENT -> SERVER: QUIT 2020-05-31 03:03:51 SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting