Duplicate room lists appearing under room finder, Please help to resolve this ASAP as this is coming in Online and Offline Mode both.

Hi,

Based on my research, the room list behavior you described is the expected behavior in Outlook. When we use a Room List  for a meeting, it is stored in the  Most Recently Used entries in the registry. When we create a new meeting, we will see this MRU entry in the top of the Room Lists . The same Room List will be seen again in the drop down which is accessed from the Exchange Server.

To prevent the duplicate entries seen in the Room List, modify the below registry entry with blank data to disable the  Most Recently Used  Room List in Outlook:

HKEY_CURRENT_USER\Software\Microsoft\Office\xx.0\outlook\preferences (xx.0 is the version number of your Outlook)
REG_SZ: RoomFinderRecentRoomList
Value: clear the value data

Hope this helps.

Regards,

Steve Fan
TechNet Community Support