Hi All, I am looking for help in the following topic: We have 3CX v15 Pro installed. I was able to set up a test system, and now I would like to start to add phones and extension to the system. I can do everything fine, the phones are registered, they have the green circle on the right side of them in the 3CX manager. But I cannot make any phone calls. At this stage I just want to call another extension from my extension, but I have the error message "Forbidden". I have the same error message with all the extension, and for softphones, and IP phones as well. I presume this happens because I changed the IP address of the 3CX server. How can I resolve this issue? Tanks for any help in advance.