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

I had the same problem.
I wanted to view my diagram, which I created the same day at work, at home. But I couldn't because of this message.
I found out that the owner of the database was the user of my computer -as expected. but since the computer is in the company's domain, and I am not connected to the company's network, the database couldn't resolve the owner.

So what I did is change the owner to a local user and it worked!!
Hope this helps someone.

You change the user by right-click on the database, properties, files, owner