We are having an issue that all users are reporting. For some reason they are losing their shared calendars. It appears to be company wide and random. A user will close outlook and when they open it again they have no shared calendar and have to reconnect to the share. Sometimes they have no issues at all. It is a new 2008 r2 server with Exchange 2010. The event logs are clean and the users are reporting that they don't get any errors. I ran ping tests from the exchange server for 24 hours and to a workstation and to an outside source and never dropped a packet. Any suggestions would be great. The users are using a mix of Office 2003 to 2010.