尝试使用带有 office 365 oauth2 accesstoken 的 swiftmailer 发送邮件时，在 smtp 上无法验证错误

Question

I am trying to send mails using swiftmailer and office 365 which failed to authenticate. I have purchased an office 365 account, azure subscription. My environment is php. Steps I did:

1. Created office 365 account
2. Created an app in Azure AD
3. created client secret
4. Set Authentication as "Accounts in any organizational directory (Any Azure AD directory - Multitenant)"
5. set API Permissions
6. Downloaded Microsoft Graph sdk to generate accessToken
7. I generated accesstoken and used the it on swiftmailer transport as password and setting the auth type as "XOAUTH2"

Here is the list of screenshots supporting above activity.

Athentication settings

API Permissions

I used below sample code from "https://github.com/microsoftgraph/msgraph-sdk-php" to get accesstoken.

    $guzzle = new \GuzzleHttp\Client();
$url = 'https://login.microsoftonline.com/' . $tenantId . '/oauth2/v2.0/token';
$token = json_decode($guzzle->post($url, [
    'form_params' => [
        'client_id' => $clientId,
        'client_secret' => $clientSecret,
        'scope' => 'https://graph.microsoft.com/.default',
        'grant_type' => 'client_credentials',
    ],
])->getBody()->getContents());
$accessToken = $token->access_token;

Below is the complete code

require_once 'swift/vendor/autoload.php';
require_once 'graph/vendor/autoload.php';




$tenant_id = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
$client_id = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
$clientSecret = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
//$graphMailer = new graphMailer($tenant_id, $client_id, $secret_id);

$guzzle = new \GuzzleHttp\Client();
$url = 'https://login.microsoftonline.com/' . $tenant_id . '/oauth2/v2.0/token';
$token = json_decode($guzzle->post($url, [
    'form_params' => [
        'client_id' => $client_id,
        'client_secret' => $clientSecret,
        'scope' => 'https://graph.microsoft.com/.default',
        'grant_type' => 'client_credentials',
    ],
])->getBody()->getContents());
$accessToken = $token->access_token;


// echo $accessToken;




$transport = (new Swift_SmtpTransport('smtp.office365.com', 587, 'tls'))
    ->setAuthMode('XOAUTH2')
   ->setUsername('sender@Testmail699.onmicrosoft.com')
    ->setPassword($accessToken)
;

$transport->start();

$mailer = new Swift_Mailer($transport);

$message = (new Swift_Message('Wonderful Subject'))
  ->setFrom(['sender@Testmail699.onmicrosoft.com' => 'Anish V M'])
  ->setTo(['toaddresss@gmail.com', 'toaddresss@gmail.com' => 'Anish'])
  ->setBody('Here is the message itself')
  ;

// Send the message
$result = $mailer->send($message);

echo $result;

I am wondering if any one can point me in right direction. Or tell me if I miss something.

Thanks

Answer 1

Disabling one setting on my WHM root login solved the failed to authenticate error on smtp for me:

WHM > Home > Server Configuration > Tweak Settings >
Restrict outgoing SMTP to root, exim, and mailman (FKA SMTP Tweak) [?]