OIT Home > OIT Knowledge Base Search Knowledge Base: How do I open a Resource Mailbox Room in Office 365? To open a Resource Mailbox Room in Office 365, please follow the instructions below. 1. Login to Office 365 at office365.utk.edu 2. Click the app launcher in the upper left hand corner. 3. Choose Calendar. 4. Right click on My calendars and select Open calendar (If you have your account set up in Outlook, you may use the Rooms heading instead of the My calendars) 5. Type in the name of the Room in the From Directory field and then choose Search Directory. Choose the Room and then click Open Need more help?