Send email via Gmail SMTP server in PHP

2026-03-11 23:20:55 SERVER -> CLIENT: 220 smtp.gmail.com ESMTP 586e51a60fabf-4177e72b40asm3460561fac.20 - gsmtp
2026-03-11 23:20:55 CLIENT -> SERVER: EHLO 1st-choice-formations.co.uk
2026-03-11 23:20:55 SERVER -> CLIENT: 250-smtp.gmail.com at your service, [204.12.204.170]250-SIZE 35882577250-8BITMIME250-STARTTLS250-ENHANCEDSTATUSCODES250-PIPELINING250-CHUNKING250 SMTPUTF8
2026-03-11 23:20:55 CLIENT -> SERVER: STARTTLS
2026-03-11 23:20:55 SERVER -> CLIENT: 220 2.0.0 Ready to start TLS
2026-03-11 23:20:55 CLIENT -> SERVER: EHLO 1st-choice-formations.co.uk
2026-03-11 23:20:55 SERVER -> CLIENT: 250-smtp.gmail.com at your service, [204.12.204.170]250-SIZE 35882577250-8BITMIME250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH250-ENHANCEDSTATUSCODES250-PIPELINING250-CHUNKING250 SMTPUTF8
2026-03-11 23:20:55 CLIENT -> SERVER: AUTH LOGIN
2026-03-11 23:20:55 SERVER -> CLIENT: 334 VXNlcm5hbWU6
2026-03-11 23:20:55 CLIENT -> SERVER: <credentials hidden>
2026-03-11 23:20:55 SERVER -> CLIENT: 334 UGFzc3dvcmQ6
2026-03-11 23:20:55 CLIENT -> SERVER: <credentials hidden>
2026-03-11 23:20:55 SERVER -> CLIENT: 535-5.7.8 Username and Password not accepted. For more information, go to535 5.7.8 https://support.google.com/mail/?p=BadCredentials 586e51a60fabf-4177e72b40asm3460561fac.20 - gsmtp
2026-03-11 23:20:55 SMTP ERROR: Password command failed: 535-5.7.8 Username and Password not accepted. For more information, go to535 5.7.8 https://support.google.com/mail/?p=BadCredentials 586e51a60fabf-4177e72b40asm3460561fac.20 - gsmtp
SMTP Error: Could not authenticate.
2026-03-11 23:20:55 CLIENT -> SERVER: QUIT
2026-03-11 23:20:55 SERVER -> CLIENT: 221 2.0.0 closing connection 586e51a60fabf-4177e72b40asm3460561fac.20 - gsmtp
SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting

Mailer Error: SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting