The objects you are adding to the designer use a different data connection than the designer is currently using
The objects you are adding to the designer use a different data connection than the designer is currently using. Do you want to replace the connection used by the designer?
When you add items to the Object Relational Designer (O/R Designer), all items use one shared data connection. (The design surface represents the DataContext, which uses a single connection for all objects on the surface.) If you add an object to the designer that uses a data connection that differs from the data connection currently being used by the designer, this message appears. To resolve this error, you can choose to maintain the existing connection. If you make this choice, the selected object will not be added. Alternatively, you can choose to add the object and reset the DataContext connection to the new connection.
Note
If you click Yes, all entity classes on the O/R Designer are mapped to the new connection.
To replace the existing connection with the connection used by the selected object
Click Yes.
The selected object is added to the O/R Designer, and the DataContext.Connection is set to the new connection.
To continue to use the existing connection and cancel adding the selected object
Click No.
The action is canceled. The DataContext.Connection remains set to the existing connection.