To Using the Exim Mail Queue Manager in WHM
Exim is the mail software that runs on your server to control email delivery, there are mail queue management options you can use with Exim directly via the command line.
Step 1 : Log into WHM.
Step 2 : Find the Email menu.
Step 3 : Go to Mail Queue Manager.
Step 4 : In the Search box type in firstname.lastname@example.org.
Step 5 : From the Select Query drop-down and select Search Recipients.
Step 6 : In Search Type Click on Begins With.
Step 7 : Click on the calendar icon and Specify the Start Date and End Date.
Step 8 : Next, specify the Start Time and End Time.
Step 9 : Then, click on Run Report.
Step 10 : We can see that our messages to email@example.com are Frozen.
This means that Exim has detected an error trying to deliver the message, and it is going to hold the message and try again later.
Step 11 : Click on the magnifying glass icon to view the message in a new window.
In this message we can see that it’s not delivering to firstname.lastname@example.org because their mail server is giving us back the error of Mailbox quota exceeded.
Step 12 : At the top of the message you can choose to Delete Message which will completely remove it from the mail queue.
you can choose to Deliver Message Now which will attempt to send the message again, in this case if the user has freed up some space on their email account it should go through successfully now.
That’s it !!