Upgrade SQL Server compact 3.5 to 4.0

Hi,

I am not to able run my VB project since it was giving error saying upgrade your databasa file from 3.5 to 4.0. The following error message i am getting ..

Warning1 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.00 LibraryManagementSystem

Could you please some guide to sort out this problem