I got Sieve up and working on Cyberpanel 2.1.1 Centos 7
What I noticed was that Cyberpanel’s dovecot version was 2.3 but the dovecot-pigeonhole available was not for that version.
I tried downgrading but that did not work since the configurations of the newer dovecot was different and caused “Authentication Failed” when logging in. So I had to go back up to version 2.3
These are my steps:
N.B. Step one will update dovecot to the latest version. Please make sure to keep track of your current version in order to rollback if configuration files clash.
What you are aiming to do is to get dovecot-pigeonhole the same version as your current setup.
First setup dovecot repository following this link:
Secondly, follow instructions in this link.