I found this to happen when I open a document as a different type. For example, I usually like to include UML diagrams and database diagrams for a project in the same document.
Unfortunately, I found that the Model Explorer and UML menus would not be displayed in the template with the database template, and the Database Menu and Database Properties would not appear when creating the UML template file.
All I can offer is to make sure that you open the correct type of template, and you should be fine.
Brian vanderbusch
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