Microsoft SQL Server Management Studio Diagram Error

Problem/Error/Issue

Microsoft SQL Server Management Studio  Database diagram failed to open when you connect to SQL Server Database remotely from another computer

Solution:

The error above caused due to the following reason

The MSSMS Database Diagram does not have a valid owner

In SQL Server Management Studio do the following:

1. Right Click on your database, choose properties
2. Go to the Options Page
3. Go to the Files Page
4. Enter "sa" or "other sql server user which is not mapped into said database diagram"
5. Hit OK

After doing this, You will now be able to access the Database Diagrams.