2026-05-29 18:41:43 SERVER -&gt; CLIENT: 220-sg2plzcpnl487150.prod.sin2.secureserver.net ESMTP Exim 4.99.2 #2 Fri, 29 May 2026 11:41:43 -0700 220-We do not authorize the use of this system to transport unsolicited, 220 and/or bulk e-mail.<br>
2026-05-29 18:41:43 CLIENT -&gt; SERVER: EHLO thebookflight.com<br>
2026-05-29 18:41:43 SERVER -&gt; CLIENT: 250-sg2plzcpnl487150.prod.sin2.secureserver.net Hello thebookflight.com [184.168.115.157]250-SIZE 52428800250-LIMITS MAILMAX=10 RCPTMAX=50000250-8BITMIME250-PIPELINING250-PIPECONNECT250-AUTH PLAIN LOGIN250 HELP<br>
2026-05-29 18:41:43 CLIENT -&gt; SERVER: AUTH LOGIN<br>
2026-05-29 18:41:43 SERVER -&gt; CLIENT: 334 VXNlcm5hbWU6<br>
2026-05-29 18:41:43 CLIENT -&gt; SERVER: [credentials hidden]<br>
2026-05-29 18:41:43 SERVER -&gt; CLIENT: 334 UGFzc3dvcmQ6<br>
2026-05-29 18:41:43 CLIENT -&gt; SERVER: [credentials hidden]<br>
2026-05-29 18:41:45 SERVER -&gt; CLIENT: 535 Incorrect authentication data<br>
2026-05-29 18:41:45 SMTP ERROR: Password command failed: 535 Incorrect authentication data<br>
SMTP Error: Could not authenticate.<br>
2026-05-29 18:41:45 CLIENT -&gt; SERVER: QUIT<br>
2026-05-29 18:41:45 SERVER -&gt; CLIENT: 221 sg2plzcpnl487150.prod.sin2.secureserver.net closing connection<br>
SMTP Error: Could not authenticate.<br>
ERROR: SMTP Error: Could not authenticate.