Database Diagram Support Objects cannot be Installed … no valid owner

Question

I tried to create a database diagramm with SQL Server 2008, but an error occurs:

Database diagram support objects cannot be installed because this dat

Answer 1

This fixed it for me. It sets the owner found under the 'files' section of the database properties window, and is as scripted by management studio.

USE [your_db_name]
GO
EXEC dbo.sp_changedbowner @loginame = N'sa', @map = false
GO

According to the sp_changedbowner documentation this is deprecated now.

Based on Israel's answer. Aaron's answer is the non-deprecated variation of this.