This project references an earlier version of SQL Server Compact that has no designer support in this version of Visual Studio. ...

This project references an earlier version of SQL Server Compact that has no designer support in this version of Visual Studio. To continue without designer support, download SQL Server Compact 3.5 from the Microsoft Download Center (http://go.microsoft.com/fwlink/?LinkId=229598). To upgrade your assets to SQL Server Compact 4.0 and enable designer support, open the project and use the Add Connection dialog box to create a connection to the database.