How to add .mdf file to Data Connections in Server Explorer

Question

Hello guys
I am developing a shopping cart in AP.NET. 2 days ago i created a database in "SQL SERVER 2008 R2". It was created successfully and everything went fine. I then copied that Database named "ESTORE" to the App_Data of my Project. But now i want to add this in "Server Explorer => Data Connections => Add Data Connection". and everytime it gives me an error like an attempt to attach an auto-named database for file C:\Users\cYpH3R x3r0\My Documents\Visual Studio 2010\Websites\New\App_Data\ESTORE.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.

Link is given here, that describes my problem best.
http://i1066.photobucket.com/albums/u401/sherry1232/errorpng.png

Sorry if that questions sounds ugly, i am new to ASP.NET and SQL Server (Recently Switched from PHP)