One thing to be careful about is that SBS includes DNS services by default and DNS randomly sets aside 2500 ports in the ephemeral port range between 49152 and 65535. Does that range look familiar? It should as most IP Office applications fall into that range. I have seen this on more than one occasion use the ports needed by Voicemail Pro which prevents the VMP service from starting.
There is a document about it:
Here are the ports that conflict:
UDP 49152-53247* RTP/RTCP Dynamically allocated ports used during VoIP calls for RTP and RTCP traffic. The port range can be adjusted through the System | Gatekeeper tab.
UDP 50791 IPO Voicemail To voicemail server address.
UDP 50793 IPO Solo Voicemail From IP Office TAPI PC with Wave drive user support.
UDP 50794 IPO Monitor From the IP Office Monitor application.
UDP 50795 IPO Voice Networking Small Community Network signalling (AVRIP) and BLF updates. Each system does a broadcast every 30 seconds. BLF updates are sent required up a maximum of every 0.5 seconds.
UDP 50796 IPO PCPartner From an IP Office application (for example Phone Manager or SoftConsole). Used to initiate a session between the IP Office and the application.
UDP 50797 IPO TAPI From an IP Office TAPI user PC.
UDP 50798 (UDP) IP Office Manager and UpgradeWizard
UDP 50799 IPO BLF Broadcast to the IP Office LAN and the first 10 IP addresses registered from other subnets.
UDP 50800 IPO License Dongle To the License Server IP Address set in the IP Office configuration.
UDP 50801 EConf Conference Center Service to IP Office.
TCP 50802 Discovery IP Office discovery from Manager.
TCP 50804* HTTP IP Office configuration settings access.
TCP 50805* HTTPS TLS Secure
TCP 50808* HTTP IP Office system status access.
TCP 50812* HTTP IP Office security settings access.
TCP 50813* HTTPS TLS Secure
Kyle Holladay
ACSS & APSS SME Communications
MCP/MCTS Exchange 2007
Adtran ATSA, Aruba ACMA
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