Hi. I'm new to ASP.net and I'm having a bit of trouble with loading information in from web.config. I've stored my database connection in the web.config and the rest of the code is in my code behind file. Here is the code behind file followed by the web.config extract. The error is caused on this line SqlConnection conn = new SqlConnection(strConnection); :

By the way, the database connection loads successfully and information is brought back when I hard code the string into the connection method.

ASP.NET Syntax (Toggle Plain Text)

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
 
public partial class testDB : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
      try
      {
        String strConnection = ConfigurationManager.ConnectionStrings["DBConnection"].ToString();
 
        //newLabel.Text = "Connection = " + strConnection;
        SqlConnection conn = new SqlConnection(strConnection);
        SqlCommand comm = new SqlCommand("select * from test_tab",conn);
 
        conn.Open();
        System.Diagnostics.Debug.WriteLine("ok");
 
        SqlDataReader reader = comm.ExecuteReader();
 
        while (reader.Read())
        {
          newLabel.Text += reader["name"] + "<br />\n";
        }
 
        reader.Close();
        conn.Close();
      }
      catch (InvalidOperationException eve)
      {
        System.Diagnostics.Debug.WriteLine("Test"+eve.Message);
        newLabel.Text = "Test" + eve.Message + "<br />" + eve.ToString();
      }
    }
}

using System; using System.Collections; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Xml.Linq; using System.Data.SqlClient; public partial class testDB : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { try { String strConnection = ConfigurationManager.ConnectionStrings["DBConnection"].ToString(); //newLabel.Text = "Connection = " + strConnection; SqlConnection conn = new SqlConnection(strConnection); SqlCommand comm = new SqlCommand("select * from test_tab",conn); conn.Open(); System.Diagnostics.Debug.WriteLine("ok"); SqlDataReader reader = comm.ExecuteReader(); while (reader.Read()) { newLabel.Text += reader["name"] + "<br />\n"; } reader.Close(); conn.Close(); } catch (InvalidOperationException eve) { System.Diagnostics.Debug.WriteLine("Test"+eve.Message); newLabel.Text = "Test" + eve.Message + "<br />" + eve.ToString(); } } }

ASP.NET Syntax (Toggle Plain Text)

 
  <connectionStrings>
    <add name="DBConnection" connectionString="Server=localhost\\SQLExpress;Database=test;Integrated Security=True" providerName="System.Data.SqlClient" />
  </connectionStrings>

<connectionStrings> <add name="DBConnection" connectionString="Server=localhost\\SQLExpress;Database=test;Integrated Security=True" providerName="System.Data.SqlClient" /> </connectionStrings>

The error I'm getting from the exception is:

ASP.NET Syntax (Toggle Plain Text)

TestInstance failure.
System.InvalidOperationException: Instance failure. at System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, ......

TestInstance failure. System.InvalidOperationException: Instance failure. at System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, ......

Try with this connection string in the web.config file

ASP.NET Syntax (Toggle Plain Text)

  <connectionStrings>
    <add name="DBConnection" connectionString="Data Source=localhost\SQLExpress;Initial Catalog=test;Integrated Security=True" providerName="System.Data.SqlClient" />
  </connectionStrings>

<connectionStrings> <add name="DBConnection" connectionString="Data Source=localhost\SQLExpress;Initial Catalog=test;Integrated Security=True" providerName="System.Data.SqlClient" /> </connectionStrings>

Right click on your service in the Service Control Manager and you will notice a "Log on" tab that probably is using "Local System Account". This means your ASP.NET webserver is running under your user account (thus integrated authentication works) but IIS is running under another account, and integrated authentication breaks.

You shouldn't change anything about the service, you should change the connection string to include a user defined on the SQL server. Undo your changes, add a user to SQL server, update your connection string, then it should be working.