For Voxbi Team to work properly, the following ports of your firewall must be open between the clients PC and destination in both directions:

443 (tcp)voxbi.teamVoxbi Webpage
443 (tcp)hpp.mixvoip.comVoxbi API for call/extension status
443 (tcp)$username.mixvoip.orgTempus => HR pro module
80,443 (tcp)$username.mixpbx.netPhone Settings
123 (udp,tcp)ntp.mixvoip.comNetwork Time Protocol
5060 (udp,tcp)$username.mixpbx.netCall Signaling => PBX
5061 (tcp)$username.mixpbx.netSIP TLS
5000 – 50000 (udp)$username.mixpbx.netRTP => Voice Communication
8088 – 8089 (tcp)$username.mixpbx.netWebRTC Signalling
3478 – 3479 (udp)stun.mixvoip.comNegotiation for NAT cases

$username is to be changed by the name of the PBX you use at Mixvoip

PBXs installed at the customer’s site may have different network interfaces and thus different IPs.