Microsoft Remote Connectivity Analyzer
Developed by the Microsoft Exchange Team, Remote Connectivity Analyzer is a bevy of tools rolled into one. On the Exchange side, you can perform ActiveSync connectivity tests, Exchange Web Services connectivity tests, Outlook connectivity tests (both Outlook Anywhere and Autodiscover), and Internet email tests (POP, IMAP, inbound/outbound SMTP). There are Lync/OCS tests, Office 365 tests, client tests, and a new Message Analyzer to analyze message headers. You can access the tool online or use Exchange Toolbox, which links you to the Remote Connectivity Analyzer site. Select a test type from the Exchange section, provide your credentials, and run the test. Results provide detailed information on where problems reside in your environment and how to resolve them.