In this office, most of us are using Outlook 2007, while a few of us uses Outlook 2010. For Outlook 2007, we are able to view other people's free busy information after hacking the registry of HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Options\Calendar and enter a new DWORD value data called 'UseLegacyFB' and set the value as 1. Once we do that, we are able to view people's free/busy information.
I don't know what to do with the Outlook 2010, since hacking the registry and updating windows did not work.
Help? 🙁
Best Answer
It sounds like the Exchange 'Availability Service' is not functioning correctly on your Client Access Server.
In Exchange 2007, Free/Busy information is available via two technologies. The old/legacy system is storing it in Public Folders, whereas the new tech is via a Web Service called the Availability Service.
Outlook 2007 can be set to use the old Free/Busy tech using the UseLegacyFB registry key, but Outlook 2010 has no support for this.
Please have a look at this Microsoft TechNet article on "Troubleshooting Free/Busy Information for Outlook 2007"