554 Nemesis ESMTP Service not available Transaction failed Reject due to policy restrictions.

Please note that, if your email header is not RFC 5321 and RFC 5322 compliant, your message will be rejected by our system.

This includes the following:

• The following email headers included in your message must be syntactically correct: Date, From, Sender, To
• The following headers included in your email must be limited to just one each: BCC, CC, Date, From, Sender, Subject, To

Therefore, we would advise you to check that the above mentioned information provided by your system is correct. Should you need additional support, please contact your System Administrator.