====== Exim4 - Remove exim version number ======

Open the file /etc/exim.conf and find the key smtp_banner, then change that line in this way :

From

<code>
smtp_banner = "${primary_hostname} ESMTP Exim ${version_number} \ 
</code>

To

<code>
smtp_banner = "${primary_hostname} ESMTP \
</code>