We are running Exchange 2007 with most of our clients using Office 2003 (Outlook 2003). We are in the process of upgrading our Office environment from 2003 to 2010. In this mixed environment (Outlook 2003 and 2010 hitting Exchange 2007 servers) we are having problems with people opening shared calendars. In particular when a Outlook 2003 user tries to open a shared calendar of someone using Outlook 2010 they can open the calendar and see the entries. However, if they try to open a specific calendar event it will not show them the details of the event. The default access to all calendars is set to "reviewer".
Outlook 2003 users have no problem opening and viewing details of other 2003 users. And 2010 users have no issues opening and viewing details of other 2010 users or 2003 users. The issue only exists when a 2003 user tries to look at calendar entry details of a 2010 user.
Any help would be greatly appreciated since we are an organization of 14,000+ and we will be working in this mixed Outlook 2003/2010 environment for some time.