Problems ith Connection string to SQL Express

My application is usningtraditional connection string:

<

addkey="DbConnection"value="driver={SQL Native Driver}; provider=SQLNCLI;server=localhost;trusted_connection=yes;database=ebay" />

It works fine with database attached to SQL Server, how do I make this working with SQL Express attachable file in data directory?

I have tried this, but it does not work:

Provider=SQLNCLI;Server=RAF001\SQLExpress;AttachDbFilename=..\TestSite\App_Data\ebay.mdf;Database=ebay;Trusted_Connection=Yes;