Voicemail silent

[khaled-fahmy]

When i call voicemail from internal network i hear enter your pin announcement normally. when i connect through VPN i still can dial 7777 but i hear silence however call counter is counting so i reached voicemail but silent. any idea what ports/protocols to check on firewall  

[Jaime Valencia]

One-way audio, no audio is most usually either routing issues, or as you pointed out, ACL/FW/etc blocking the communication between endpoints.

The security guide for CUC contains the ports that are used, review the one for your version.