One needs to update /etc/ngcp-config/templates/etc/ngcp-faxserver/faxserver.conf.tt2 if he wants to use custom content in the fax and e-mail templates that are used by Faxserver to generate the actual fax or e-mail. This may be done under the "User templates" section in the file.

Applying new Faxserver configuration

Once the above mentioned configuration files have been modified the new settings must be applied:

ngcpcfg apply 'Configured fax server'
ngcpcfg push all