This is really good. I have used it before and it looks really sweet now
Check it out: Announcing the release of Exchange Server Remote Connectivity Analyzer and https://www.testexchangeconnectivity.com/
Have you ever installed an Exchange server and wanted to verify your Internet facing services were setup and configured properly? Things like Exchange ActiveSync, AutoDiscover, Outlook Anywhere (RPC/HTTP), and inbound email. Sure there are cmdlets included in Exchange 2007 like test-ActivesyncConnectivity and test-OWAConnectivity, but these tests can only be run inside your network and effectively only test your internal network connectivity. Or what if you get a call or an escalation regarding one of these services not working? How do you verify if just this user or everyone has a problem? And if there is a problem, where do you start troubleshooting? Is it a DNS problem? Is it a certificate problem? Is a port not open on the firewall?