I’m sorry, but that’s simply an idiotic a nonsensical expectation of any piece of server software*. You set it up incorrectly, likely without reading the documentation, and you’re blaming the software. It’s 99% likely that the problem is 100% on you. As it is right now, you’ve wasted your time and ours–yours in whatever time you’ve put into it that didn’t result in a working system; ours in the time responding, gaining no understanding of what the problem actually was since you’ve given us absolutely nothing to work with, and we can’t do anything to make it any better because all you’ve done is complain.
*your requirement boils down to “it’s literally impossible to misconfigure it.” That isn’t true of CentOS, it isn’t true of Koozali/SME (and the order you put those in is, well, weird–it’s been ages since Mitel had anything to do with it as a standalone product), and it isn’t true of any other piece of software less trivial than Hello World. If it can be configured, it can be misconfigured. And nobody can build a foolproof product because fools are so damned clever sometimes.