I am unable to make US and Canada calls whenever I try it say me " Call forbidden by administrator". But I am able to make calls in UK. Please check and let me know.
It usually means that that when you set up the PBX you restricted the calling to certain countries (+ country codes). However, SMB settings seem to differ.
Here is a thread dealing with international calling on SMB.
I am new to 3cx and using the guides i have managed to setup 85% of the system with virtually no problems. The odd glitch had to be rectified but I managed to sort them.
International calling on the other hand i can't seem to grasp what i need to set and the guide is based on American calling which confused me. Has anyone got a simple guide / screenshot who is based in the UK of the setup for international calling that i could use to help me set it up our system.