How to find out why an email was rejected

Introduction

Sometimes, a server will reject an inbound email, but the exim_mainlog logfile only shows that the message was rejected. To find out why the server rejected the message, you need to check the exim_rejectlog log file.

Procedure

1. Access the server's command line as the 'root' user via SSH or "Terminal" in WHM.
2. Search the exim_rejectlog for the recipient and sender email addresses.

   grep -B 10 -A 100 $recipeient@domain.tld /var/log/exim_rejectlog | grep $sender@sendingdomain.tld -B 4 -A 100

   Please note that "$recipeient@domain.tld" and "$sender@sendingdomain.tld" must be replaced with the recipient and sender email addresses.
3. Review the output for the rejection reason.