Error: Database diagram support objects cannot be installed because this database does not have a valid owner

If you have been using the database diagrams from SQL Server 2000 onwards and when it is upgraded to SQL 2005 you might get the following error: TITLE: Microsoft SQL Server Management Studio ------------------------------ Database diagram support objects cannot be installed because this database does not have a valid owner. To continue, first use the Files page of the Database Properties dialog box or the ALTER AUTHORIZATION statement to set the database owner to a valid login, then add the database...(<a href="http://sqlserver-qa.net/blogs/tools/archive/2007/09/06/error-database-diagram-support-objects-cannot-be-installed-because-this-database-does-not-have-a-valid-owner.aspx">read more</a>)<img src="http://sqlserver-qa.net/aggbug.aspx?PostID=1908" width="1" height="1">