Troubleshooting "Invalid License File. Incorrect authority delivering the license" Error

Symptoms

When trying to access WHM you are presented with this error:

Invalid License File. Incorrect authority delivering the license.

Also attempting to update the license information fails with this error message:

/usr/local/cpanel/cpkeyclt

DNS::Unbound object version 0.19 does not match $DNS::Unbound::VERSION 0.20

This is usually indicative of some missing cPanel-required packages specifically this package:

cpanel-perl-530-DNS-Unbound-0.20-1.cp1186

The required packages all need to be installed before the license can be updated.

First, make sure that RPM is working and responsive:

/scripts/find_and_fix_rpm_issues

In case RPM is unresponsive then you can visit this link to see how to repair RPM's database:

https://support.cpanel.net/hc/en-us/articles/360052489913-How-to-repair-an-RPM-database

After making sure RPM is working you need to run this command to install all the missing cPanel-required packages:

/scripts/check_cpanel_rpms

In the output, you will see the name of the missing package mentioned above. After this you can run the command again to update the license:

usr/local/cpanel/cpkeyclt
Updating cPanel license...Done. Update succeeded.