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Within the Outlook inbox, select New Items > Meeting
Alternatively, within the Outlook calendar, click on the New Meeting icon in the task bar
Click on the Scheduling Assistant icon in the task bar
Click on Add Rooms… at the bottom left hand corner of the window
Search for the desired room name in the search bar or browse through the list of rooms
Select the room(s)
e.g. Room - AIEN 111; Room - AIEN 210B
and then click OK
Using Room Finder
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