Office 365 (Known Issues) - Reserving Rooms for Meetings in Outlook on the Web
OotW (Outlook on the Web) can only display 100 rooms when using the "Add Room" tool to reserve a room for a meeting. Therefore, when reserving a resouce via the "add room" tool in Outlook on the Weblication, only part of UWM's total list of resources will be displayed.
Resolution Status: Unresolved
Workaround
To reserve a room, enter it in the "Attendees" field instead of in the "Location" field using this convention: Resource-BldgAbbreviation-RoomNumber (e.g., resource-BOL-210).
NOTE: See the "Office 365 (Outlook on the Web) - Reserving a Room" document for steps and more information.