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503 Bad sequence of commands if count($this->all_recipients) == count($bad_rcpt) · Issue #156 · PHPMailer/PHPMailer · GitHub
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smtp.office365.com starttls 503 Bad sequence of commands · Issue #1354 · swiftmailer/swiftmailer · GitHub
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SMTP response: 503 Bad sequence of commands · Issue #666 · forkcms/forkcms · GitHub
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