I Cannot Connect To SQLSERVER Database

In SQLserver Admin, ANDONASPNET is setup as a 'Server Admin'



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Connection string is set in the web.config file.

<configuration>



<connectionStrings>

<add name="SqlServerEx"

connectionString="Data Source=LOCALHOSTSQLEXPRESS;Initial Catalog=DB2;Integrated Security=SSPI;"

providerName="System.Data.SqlClient;"></add>

</connectionStrings>



<appSettings/>



<system.web>

.......................................................................







protected void Button2_Click(object sender, EventArgs e)

{

string connStr = WebConfigurationManager.ConnectionStrings["SqlServerEx"].ConnectionString;

SqlConnection con = new SqlConnection(connStr);

TextBox3.Text = connStr;

try

{

con.Open();

TextBox2.Text = "<b> Server Verison::</b>" + con.ServerVersion;

TextBox2.Text += "<br /><B>Connection Is::</B> " + con.State.ToString();

}

catch (Exception err)

{

TextBox2.Text = "Error reading Database. ";

TextBox2.Text += err.Message;

}

finally

{

con.Close();

TextBox2.Text += "<BR><B>CONNECTION::" + con.State.ToString() + "</B>";

}

}

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This is the error message I am getting:

"Error reading Database. Instance failure."