Install from git

This was the recommended install method for versions up to 2.3.3. When running in _dev from version 2.3.4 and above, only the English language is available. If you need support for other languages, you must run the client in development mode (for testing) append ?dev=1 in your browser.

Or install via zmzimletctl deploy.

[root@myzimbra ~]# su zimbra
[zimbra@myzimbra ~]# zmzimletctl undeploy tk_barrydegraaff_zimbra_openpgp
[zimbra@myzimbra ~]# exit
[root@myzimbra ~]# yum install -y git 
[root@myzimbra ~]# apt-get -y install git
[root@myzimbra ~]# cd ~
[root@myzimbra ~]# rm pgp-zimlet -Rf
[root@myzimbra ~]# git clone https://github.com/Zimbra-Community/pgp-zimlet
[root@myzimbra ~]# cd pgp-zimlet
[root@myzimbra pgp-zimlet]# git checkout <latest version here>
[root@myzimbra pgp-zimlet]# chmod +rx install-dev.sh
[root@myzimbra pgp-zimlet]# ./install-dev.sh
[root@myzimbra pgp-zimlet]# su zimbra
[zimbra@myzimbra pgp-zimlet] zmprov mc default zimbraPrefZimletTreeOpen TRUE
[zimbra@myzimbra pgp-zimlet] zmmailboxdctl restart

Where 2.3.3 is the version number you are building.