Issues encountered while creating database diagrams

--Database Diagram Support Objects cannot is installed because this Database does not has a valid owner . To continue, first use the Files page of the Database Properties dialog box or the ALTER AUTHORIZATION statement to set th E database owner to a valid login and then add the database Diagram support objects.

Workaround:
1. Right click on the database and select "Properties"
2. Click "Options" on the left.
3. Select ' SQL Server 2005 (90) ' at ' Compatibility level '
4. Click "Files" on the Left
5. Enter ' sa ' in owner
6. OK

Issues encountered while creating database diagrams