How to block emails from a specific address using Exim

Issue :
How to block emails from a specific address on a cPanel/WHM server using Exim ?
Solution :
This is fairly easy to achieve with Exim.
First you’ll need to find the system filter file for Exim. This can be found out through WHM >> Main >> Service Configuration >> Exim Configuration Editor.
Towards the middle of the page, under the section ‘Filters’ , you ‘ll find the path to the file.
Open that file via SSH using your favorite editor and add the following to it :

if first_delivery
and ( (“$h_from:” contains “emailtoblock@domainname.com”)
)
then fail
endif

Exim Remove All messages From the Mail Queue

Question:

 I'm using Exim mail server under CentOS Linux. How do I remove all messages from the Exim mail queue using a shell prompt?

Answer:
Exim is a mail transfer agent (MTA) used on Unix-like operating systems. It aims to be a general and flexible mailer with extensive facilities for checking incoming e-mail.

To print a list of the messages in the queue, enter:

# exim -bp

To remove a message from the queue, enter:

# exim -Mrm {message-id}

To remove all messages from the queue, enter:

# exim -bp | awk '/^ *[0-9]+[mhd]/{print "exim -Mrm " $3}' | bash

Dallas Marlow, suggested following clean command:

# exim -bp | exiqgrep -i | xargs exim -Mrm

DELETE FROZEN MAILS

/usr/sbin/exim -bp | awk '$6~"frozen" { print $3 }' | xargs /usr/sbin/exim -Mrm

REMOVE MAILS FROM SENDER

/usr/sbin/exiqgrep -i -f (MAIL ADDRESS HERE) | xargs /usr/sbin/exim -Mrm 

OR 

/usr/sbin/exim -bp | awk '$4~"info@domain.com" { print $3 }' | xargs /usr/sbin/exim -Mrm