Ring While Busy - 3CX

Created by Alan Contreras, Modified on Thu, 11 Sep at 7:50 PM by Alan Contreras

https://www.3cx.com/community/threads/ring-all-groups-busy-extension-cant-ring-or-indicate-new-incoming-call.85447/

Step 1:
Enable on extension setting Call Forwarding, "Accept multiple calls"

Step 2:

Under Advanced>Parameters>ALLOWUSEBUSYOPTFORGROUP , set value to 1 (NOTE: This option is not supported by official 3CX standards and can cause unintended consequences, whatever that means).