Outlook

Microsoft 365 Exchange Error Code 5.2.122 – Recipient’s per hour message receive limit exceeded.

Microsoft 365 Exchange Error Code 4.7.322 – certificate-expired: Destination mail server’s certificate is expired.

Microsoft 365 Exchange Error Code 5.2.2 – Submission quota exceeded

Microsoft 365 Exchange Error Code 4.4.316 – Connection refused [Message=Socket error code 10061]

Microsoft 365 Exchange Error Code 5.7.505 – Access denied, banned recipient

Microsoft 365 Exchange Error Code 5.1.8 – Access denied, bad outbound sender

Microsoft 365 Exchange Error Code 5.7.512 – Access denied, message must be RFC 5322 section 3.6.2 compliant