The original message was received at Fri, 14 May 2021 13:28:34 GMT from m0114289.ppops.net [127.0.0.1] ----- The following addresses had permanent fatal errors ----- <simon.breslav@autodesk.com> (reason: 550 5.4.1 Recipient address rejected: Access denied. AS(201806281) [BN8NAM11FT049.eop-nam11.prod.protection.outlook.com]) ----- Transcript of session follows ----- ... while talking to autodesk-com.mail.protection.outlook.com.:

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DATA <<< 550 5.4.1 Recipient address rejected: Access denied. AS(201806281) [BN8NAM11FT049.eop-nam11.prod.protection.outlook.com] 550 5.1.1 <simon.breslav@autodesk.com>... User unknown <<< 503 5.5.2 Need rcpt command [BN8NAM11FT049.eop-nam11.prod.protection.outlook.com]