Event ID - 4001

Event Id4001
Sourcesmtpsvc
DescriptionMessage delivery to the remote domain <domain name> failed. The error message is "An SMTP protocol error occurred. . The SMTP verb which caused the error is <smtp command>. The response from the remote server is <server response>
Event InformationInformation from anew group: "550 This system has been configured to reject your mail" -"A program called Mail sweeper caused the issue; the client had added our email address to the list of banned address". MAIL - 501 bogus mail from - no info -this may happen when the email address of the sender (mail from) is invalid (wrong format) MAIL - 452 <email address>... DNS lookup for domain failed --- try again later - Cause: there is no reverse name resolution for the sender domain and the remote mail server is configured to only allow mail from servers whose IP address resolve.
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