FortiVoice Compatibility Guide
Please be aware that not all Fortivoice phones are compatible with all Fortivoice phone systems. To be more specific, the FON-H25, FON-175, and FON-375 are not compatible with the older D-Series 5.0 systems. All phone are however compatible with the new Enterprise FVE systems running 5.3.4 software. We should not be quoting the D-Series systems today and instead should only be quoting FVE system.