GMAIL SMTP Connect Fails On Server But Works On Local

I am using chilkat library to send email, it works perfectly on my local server/pc, but on live server it fails on smtp connect.

I tried both SSL and tls port.. (465/587) but both fails with same kind of error message..

following is the part of code to connect to google smtp server

//init
$smtp = new CkMailMan();
$smtp->put_VerboseLogging(true);
$smtp->put_SmtpHost('smtp.gmail.com');
$smtp->put_SmtpPort(465);
$smtp->put_SmtpSsl(true);
//connect
if(!$smtp->SmtpConnect())
{
    file_put_contents('./log/smtp_error_' . $GLOBALS['unixTime'] . '.log', $smtp->lastErrorXml());
    unset($smtp);
    echo '!failed!';
    exit();
}

and here is the log file:

  <ChilkatLog>
  <SmtpConnect ms="30066">
    <DllDate>Jun 25 2022</DllDate>
    <ChilkatVersion>9.5.0.91</ChilkatVersion>
    <UnlockPrefix>NONE</UnlockPrefix>
    <Architecture>Little Endian; 64-bit</Architecture>
    <Language>Linux PHP</Language>
    <VerboseLogging>1</VerboseLogging>
    <ensureSmtpConnection ms="30066">
      <smtpParams>
        <SmtpHost>smtp.gmail.com</SmtpHost>
        <SmtpPort>465</SmtpPort>
        <SmtpUsername></SmtpUsername>
        <SmtpSsl>1</SmtpSsl>
        <StartTLS>0</StartTLS>
      </smtpParams>
      <smtpConnect ms="30066">
        <smtpHostname>smtp.gmail.com</smtpHostname>
        <smtpPort>465</smtpPort>
        <connectionIsReady>
          <info>SMTP host changed.</info>
          <info>SMTP port changed.</info>
          <info>Need new SMTP connection, something changed!</info>
        </connectionIsReady>
        <smtpSocketConnect ms="30066">
          <socket2Connect ms="30066">
            <connect2 ms="30066">
              <hostname>smtp.gmail.com</hostname>
              <port>465</port>
              <ssl>True</ssl>
              <connectImplicitSsl ms="30066">
                <info>Clearing TLS client certificates.</info>
                <connectSocket ms="30066">
                  <domainOrIpAddress>smtp.gmail.com</domainOrIpAddress>
                  <port>465</port>
                  <connectTimeoutMs>30000</connectTimeoutMs>
                  <connect_ipv6_or_ipv4 ms="30066">
                    <info>Single-threaded domain to IP address resolution</info>
                    <info>connecting to IPV4 address...</info>
                    <ipAddress>172.253.115.108</ipAddress>
                    <createSocket>
                      <info>Setting SO_SNDBUF size</info>
                      <sendBufSize>262144</sendBufSize>
                      <info>Setting SO_RCVBUF size</info>
                      <recvBufSize>4194304</recvBufSize>
                    </createSocket>
                    <connect ms="30065">
                      <info>Waiting for the connect to complete...</info>
                      <connectTimeoutMs>30000</connectTimeoutMs>
                      <error>timeout waiting for connect to complete;</error>
                      <timeoutMs>30000</timeoutMs>
                      <failedWaitToConnect>Socket operation timeout.</failedWaitToConnect>
                    </connect>
                  </connect_ipv6_or_ipv4>
                </connectSocket>
                <error>pmConnect failed.</error>
              </connectImplicitSsl>
              <connectFailReason>6</connectFailReason>
              <ConnectFailReason>Timeout</ConnectFailReason>
              <error>A few possible causes for a connection timeout are:</error>
              <error>- The remote host is not reachable (perhaps a firewall is blocking the connection on the remote end).</error>
              <error>- Your ISP is blocking the outbound connection (this is common for SMTP port 25).</error>
              <error>- If your timeout is too short, then maybe the server is just too slow to accept the connection.</error>
            </connect2>
          </socket2Connect>
          <error>Failed to connect to SMTP server..</error>
        </smtpSocketConnect>
      </smtpConnect>
    </ensureSmtpConnection>
    <error>Failed.</error>
  </SmtpConnect>
</ChilkatLog>

i have consulted with server tech and they said, all the port 465,587,25 all is open.

so, i am so confused why it is not working?

info: it's linux server with plex

Regardless of what your server tech says, you should validate that the ports are open and eliminate at least one of the possibilities.

Here's a simple script that attempts to connect through various ports, and returns a SUCCESS or ERROR message for each.

<?php
$servers = array(
    array("ssl://www.google.com", 443),
    array("smtp.gmail.com", 465),
    array("smtp.gmail.com", 587),
);

foreach ($servers as $server) {
    list($server, $port) = $server;
    echo "<h1>Attempting connect to <tt>$server:$port</tt></h1>\n";
    flush();
    $socket = fsockopen($server, $port, $errno, $errstr, 10);
    if(!$socket) {
      echo "<p>ERROR: $server:$portsmtp - $errstr ($errno)</p>\n";
    } else {
      echo "<p>SUCCESS: $server:$port - ok</p>\n";
    }
    flush();
}