Programing a FortinetVoiceEnterprise 100E system.

We have a customer that owns a Fortinet FortiVoiceEnterprice 100E with 35 phones. We have not worked with this system before. We need to setup a following phone number for night emergencies, we need to set up voicemail for any guest in the hotel. We need to improve the functioning of this system. They own 35 of the phones so they do not want to move to a new make. We could install a new FortiVoice if needed? We are not sure about the password for the system. Can we factory reset it? We would also like to move the system to SIP lines not analog as it is now.

Please call me if you have any question.

Thank you.