The BOL of SQL server CE gives you the method to create the connection string. The only thing happening here is you are not able to give the file to the application. It can be that the BUILD ACTION of the (SDF) file might be set to nothing. change this to content.

Second thing you will have to look into is connection string you are specifying try giving it the folder in which your application is running.

By the way which version of Visual studio are you using.

Rajesh.

MBA-IT (Software Dev. & Mgmt)

SCIT 2007-09