Error code : 554 Email rejected due to security policies in Track and Trace logs

Products

• Email Security.cloud

Issue/Introduction

Sender domain registered in Email Security Cloud is unable to send an email to external 3rd party recipient and is encountering error 554 Email rejected due to security policies - https://community.mimecast.com/docs/DOC-1369#554 [8EXHpFs3OMmErUIlM4eBUg.uk40]

Environment

Email Security.cloud

Resolution

• Recipient is using Mimecast as their Email Service Provider and is blocking emails from the sender.
• Recipient should be contacted in such cases to check if there are any Security policies defined for the sender on their end and then exclude the sender so that emails can be allowed.