If you ever face this situation, you will need to create another admin user to change the password for other users. In order to do that, open a shell in your Pandora FMS server and execute following command:
/usr/share/pandora_server/util/pandora_manage.pl /etc/pandora/pandora_server.conf --create_user admin2 none 1
This will create a new administrator user called “admin2” with password “none”. You can set the username and password you like.
Now, get into Pandora FMS Console using the new admin2’s credentials, and change the password for the main user for which the password is lost. Please remember to delete or modify the new user admin2, in order to avoid security holes.