In SQL Server Management Studio do the following: Right Click on your database, choose properties Go to the Options Page In the Drop down at right labeled "Compatibility Level" choose "SQL Server 2005(90)" 3-1. choose "SQL Server 2008" if you receive a comparability error. Go to the Files Page Enter "sa" in the owner textbox. 5-1 or click on the ellipses(...) and choose a rightful owner. Hit OK after doing this, You will now be able to access the Database Diagrams.
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