MailScanner fails to start Can’t locate Sys/Hostname

If you are trying to start MailScanner on CPanel/WHM server and getting error Can’t locate Sys/Hostname

MailScanner fails to start with startup errors matching: 

Can't locate Sys/Hostname/Long.pm in @INC (you may need to install the Sys::Hostname::Long module) (@INC contains: /usr/mailscanner/usr/share/MailScanner/perl /usr/mailscanner/usr/share/MailScanner/perl /usr/...el_lib/x86_64-linux-6

If a server is using either of these ConfigServer MailScanner installer/products below, with the listed versions or lower: MailScanner Installer (msinstall) version 3.17 or lower MailScanner Front-End (MSFE) version 8.28 or lower MailScanner will not start due to the switch to Perl 5.3.0. 

This has been fixed in newer versions of MailScanner and the software should be updated per their instructions here: 

If you would like a convenient way to upgrade all of your installed ConfigServer scripts on a cPanelserver then we have provided a simple script that can do this for you:

This script will update: cmm, cmc, cmq, cse, csf, cxs, msinstall, msfe

Only those scripts that are already installed will be updated. Those that are updated are done so regardless as to whether they are the same or an older version of those available.

To use this method you must be logged into root via SSH to the server and then run:

curl -sL https://download.configserver.com/csupdate | perl

You should take care to read through the output to ensure that all the upgrades have worked as expected.