Desktop Client
Open Outlook and switch to your Calendar.
from the Ribbon, choose Open Calendar then Open Shared Calendar...
In the Search field, type the name of the calendar and press enter.
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To create/edit/delete a booked event (you must have read & write access), double click on the day to open the Untitled - Event window. Be sure to Save & Close any changes that are made.
Web Client (OWA/SUMail)
Open SUMail from your browser.
Switch to the Calendar view
Select "Add Calendar" from the left side panel.
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Select "Add from directory"
Select your account
Then begin typing the calendar name you are looking for in the "Enter a name or email address" field. For example type "Hinds Hall" to bring up a list of room calendars.