Therefore, you need to perform the test on an empty test mailbox.
A number of calendar items will be created and free/busy access will be validated.
If the test encounters any problems, it describes exactly what's causing the problem.
We are experiencing a sporadic issue where a shared calendar is not updating.
Once logged into the mailbox, the tool attempts to create and delete items in an effort to test synchronization functionality.
To access it, open Outlook and then hold down the Ctrl key and right-click the Outlook icon in the system tray.
This launches the Test E-Mail Auto Configuration utility.
In addition, if you're publishing your CAS to the Internet via a reverse-proxy solution, you must have a publishing rule that allows access to the /EWS/* path on your CAS server(s).
Whether you're troubleshooting Exchange 2010 free/busy lookups internally or externally, both Outlook 2007 and Outlook 2010 have a built-in tool that can help.
The SCP is set up when the CAS server role is installed, but you should still validate that it is working correctly.