I have the free version of 3CX (for testing) ver 10, and to test, I am using 3CX forIPhone. On the local LAN everything works fine. When outside the local LAN I use the External Server option and enter the URL that points to my home DSL where the 3CX system resides. I have verified that the URL is correct, I have opened ports 5060, 5090, and 9000-9009. The IPhone app will not register when away from the LAN. I get a authentication failure. I check the logs in the 3CX server and it shows "Credentials don't match, Check that authorization-ID and password match the ones in extension settings". These are the same credentials that I am using when on the local LAN. Can anyone give me any help on how to fix this issue.