无法连接到GMail SMTP(PHPMailer) - 证书验证失败

Question

最近在尝试通过SMTP和GMail发送邮件时遇到此错误.

Warning: stream_socket_enable_crypto(): SSL operation failed with code 1.
OpenSSL Error messages: error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed in C:\xampp\htdocs\portal\libraries\php_mailer\class.smtp.php on line 343
2017-12-05 09:48:03 SMTP Error: Could not connect to SMTP host. 
2017-12-05 09:48:03 CLIENT -> SERVER: QUIT 
2017-12-05 09:48:03 SMTP ERROR: QUIT command failed:

服务器地址为https ://gg-portal.com,SSL配置似乎正确(通过在线检查程序验证).

PHPMailer代码是......

$mail = new PHPMailer();
$mail->isSMTP();
$mail->Host = "smtp.gmail.com";
$mail->SMTPAuth = true;
$mail->Username = $this->_config["EmailUser"];
$mail->Password = $this->_config["EmailPass"];
$mail->SMTPSecure = "tls";
$mail->SMTPDebug = 1;
$mail->Port = 587;
$mail->FromName = $this->_config["Brand"];  
$mail->From     = $this->_config["EmailFrom"];
$mail->AddCC("...emailAddress...");
$mail->Subject  = "...subject...";
$mail->Body     = "...content...";
$mail->IsHTML(true);  
$mail->WordWrap = 50;
if(!$mail->Send()) {
    echo ' Message was not sent.';
    echo 'Mailer error: ' . $mail->ErrorInfo;
}

已经查看了建议证书问题的文档,尽管如上所述SSL设置似乎没问题.已经在其他地方研究过这个问题,最受欢迎的建议是绕过SSL(这是有效的)但是我不想这样做.

'context' => [
    'ssl' => [
        'verify_peer' => false,
        'verify_peer_name' => false,
        'allow_self_signed' => true
    ]
]

Answer 1

为我固定的问题我通过下载更新的根证书文件并将我的php.ini文件指向它来修复我的Windows php环境中的这个问题.似乎问题不在于gmail的证书,而在于由于Windows Server 2012不再自动更新此文件而导致过期的根证书文件.从这里下载cacert.pem:https://curl.haxx.se/docs/caextract.html .然后在php.ini中使用以下行指向它(假设您已安装openssl.dll).

openssl.cafile = {服务器上文件的路径}\cacert.pem.

修复它,我不再需要像建议那样绕过SSL/TLS验证.最终,我需要让Windows使用GPO或WSUS自动更新根证书.请参阅https://serverfault.com/questions/541922/where-to-get-root-ca-certificates-for-windows-server-now-that-microsoft-no-longe