When forwarding a number via a ring group in VoIPOffice (specifically v3.8+), the CLI is not passed through by default.
To resolve this, ensure that the trunk the call is routing out via has the caller ID set to %CALLERIDNUM%. This forces the trunk to pull the CLI from the From: header of the original inbound call.
In cases where a specific number needs to be set as CLI on the trunk, a prefix must be created to forward the call via a different trunk:
- On the customer's tenant settings page, press Other Networks.
- Enable 1 digit dialling.
- Set the prefix to any digit other than 0 or 9 and make sure the Strip Prefix option is selected.
- Set the trunk to dial out from.
- Ensure the external number in the ring group is prefixed correctly.