Sql Server Doesn't Exist Or Access Denied (ASP.NET USING C#)

hello can anybody help me in this issue:-i got two sets of connection string modules, let us say (1) working (2) not working, and here is the code for the two sets:-set (1) which is working fine:-

 private void OpenData(){System.Data.DataTable dt = new System.Data.DataTable();

// The connection string was not originally hardcoded but for some reason it was staying around when passed

// in through the constructor. It was always blank.

System.Data.SqlClient.SqlConnection cn = new System.Data.SqlClient.SqlConnection(@"data source=localhost;initial catalog=truckorder;Integrated Security=SSPI;");

//System.Data.SqlClient.SqlConnection cn = new System.Data.SqlClient.SqlConnection(_cnString);

cn.Open();

new System.Data.SqlClient.SqlDataAdapter("SELECT * FROM dealers WHERE DealerWeb like '%" + _url + "%'", cn).Fill(dt);

if(dt.Rows.Count > 0)

{_dealerid = Int32.Parse(dt.Rows[0]["dealerid"].ToString());_dealername = dt.Rows[0]["dealerName"].ToString();_dealerparent = Int32.Parse(dt.Rows[0]["dealerParent"].ToString());_usedMessage = dt.Rows[0]["usedMessage"].ToString();_rentalMessage = dt.Rows[0]["rentalMessage"].ToString();}

cn.Close();}----------------------------------------------------------------------------------------------------------------------------------------------------------------------set (2) not working fine:-private void OpenData()

{

System.Data.DataTable dt = new System.Data.DataTable();System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection ();conn.ConnectionString = "integrated security=SSPI;data source=FR011PC;persist security info=False;initial catalog=TruckOrder";



try{conn.Open();new System.Data.SqlClient.SqlDataAdapter("SELECT * FROM dealers WHERE DealerWeb like 'yalevictoria.com.au'", conn).Fill(dt);

if(dt.Rows.Count > 0){_dealerid = Int32.Parse(dt.Rows[0]["dealerid"].ToString());_dealername = dt.Rows[0]["dealerName"].ToString();_dealerparent = Int32.Parse(dt.Rows[0]["dealerParent"].ToString());_usedMessage = dt.Rows[0]["usedMessage"].ToString();_rentalMessage = dt.Rows[0]["rentalMessage"].ToString(); _dealerWeb = dt.Rows[0]["dealerWeb"].ToString();}}

finally

{conn.Close();}THE DIFFERENCE IN BOTH THE SETS IS :- The Connection String (if you look at carefully) the one which is working has localhost and the one which is not working is having FR011PC (this code is working fine on FR011PC machine name and SqlServer Name) BUTwhen i transfer FR011PC code to the localhost machine, I mean i changed to datasource from FR011PC to localhost and run its giving me SQL SERVER DOESN'T EXIST OR ACCESS DENIED.Can any body help me on this issue has this is urgent for me please...................