I have registered, configured and entered in the credentials (MyPBX) to Zoiper. It's not working. I have selected SIP. When I try to make a test call, it gives SIP 500: Service unavailable. What else do I need to do? What are the codecs?
Thanks
Hello,
Error SIP 500 is returned from the server. It is best to contact your VoIP provider for more details on that matter.