The original message was received at Sun, 18 Feb 2024 15:45:27 GMT from m0214715.ppops.net [127.0.0.1] ----- The following addresses had permanent fatal errors ----- <m.cowling2@brighton.ac.uk> (reason: 550-The email address you have attempted to send to does not exist.) ----- Transcript of session follows ----- ... while talking to mta.brighton.ac.uk.:

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DATA <<< 550-The email address you have attempted to send to does not exist. <<< 550 Contact postmaster@brighton.ac.uk for further assistance. 550 5.1.1 <m.cowling2@brighton.ac.uk>... User unknown <<< 503-All RCPT commands were rejected with this error: <<< 503-The email address you have attempted to send to does not exist. <<< 503-Contact postmaster@brighton.ac.uk for further assistance. <<< 503 Valid RCPT command must precede DATA