Exchange Administrators, Please Disable Web-based Administration For Your Router.
This is something I see far too regularly in various Exchange support forums. Admins asking why their Outlook Web Access works fine internally (i.e. from the LAN), but when they try to access it externally, they get a ’404 – Page Not Found’ error message. The answer is usually a simple one. They have web-based administration enabled at their internet-facing router. The 404 is the router saying that it can’t find the OWA subdirectory within its own web site. Even more scary – they don’t always seem to know that it’s enabled, or that you can even do that sort of thing. The sort of person that doesn’t know that is also unlikely to have changed the default admin passwords, either. Doesn’t that sound rather worrying? It certainly does to me.
So, this is one of the first things you should check for, in my opinion, as soon as you have established network access to the internet. Please, go and check your router’s admin pages, and make sure that you:
1. Change that default password, and
2. Turn off web-based admin on the external-facing interface.