How to: Upgrade Database Diagrams from Previous Editions
Database diagrams created on previous editions of SQL Server databases are upgraded automatically when database diagramming is set up on Microsoft SQL Server 2005. For more steps for setting up diagramming see How to: Set Up Database Diagram Designer.
Your computer might show different names or locations for some of the Visual Studio user interface elements in the following instructions. The Visual Studio edition that you have and the settings that you use determine these elements. For more information, see Customizing Development Settings in Visual Studio.
To upgrade legacy database diagrams
Create a database connection in Server Explorer using a member of the db_owner role to log in. For steps see How to: Connect to a Database from Server Explorer.
Expand the Database Diagram node under the database connection.
Select Yes when prompted if you want to set up database diagramming.
This will upgrade diagrams stored on the database.