[Fixed] Zentyal 3.5 NO_PUBKEY error in apt-get update

Zentyal community edition is one of the widely used application for managing infrastructure. Zentyal pushes frequent updates through Zentyal repositories.

One my get following error while upgrading Zentyal:

W: GPG error: http://archive.zentyal.org 3.5 Release: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 8E9229F7E23F4777

Solution:

Add the Zentyal 3.5 key so that apt connect to the repository.

wget http://keys.zentyal.org/zentyal-3.5-archive.asc
sudo apt-key add zentyal-3.5-archive.asc
sudo apt-get update

Note: If you face issue for Zentyal version 3.4 then replace 3.5 to 3.4 in the link.