To change the join password on the server follow these steps;
1.) Login to the web control-panel, http://control.branzone.com
2.) Browse to; Voice Servers > YOUR_SERVER > Voice Server Configuration
3.) Once in the configuration page select to edit the "ventrilo_srv.ini" file.
4.) Under the section "Authentication Settings" select the drop down menu next to 'Auth' and set it to "Global Password".
A password box will now appear below the drop down menu that you can enter the server join password in. Once you have saved the changes you will need to restart your server for the new password to take affect.
