When saving a calendar item, if we do not select a query we receive a pop-up that says Query: This field must be completed prior to saving.
We need to select a Category and Query within the Calendar Item in the Invite Accounts section. The query All Accounts in the Base category will automatically be populated when creating a new entry. The accounts in the query results will not be added as attendees unless we click the button Invite Accounts From Query. We do not need to invite the accounts from the query to be able to save the Calendar Item, it only needs to be selected in the drop down menus.