I am getting a Network or instance related error with my ap

Question

I have a application in which in app.config i mentioned my connection string such as 

 

 

<add name="DMS_2008_Data.Properties.Settings.Default.DataConnection"

connectionString="Data Source=ASPKCO-DANISH\SQLEXPRESS1;Initial Catalog=DMS2008;Integrated Security=True;Connect Timeout=30"

providerName="System.Data.SqlClient" />

 

and in code i am using this line

public ClsUserLoging IsValidLog(string UserID, string PassWord)

{

try

{

objClsUsers = null;

con = new SqlConnection(DMS_2008_Data.Properties.Settings.Default.DataConnection.ToString());

con.Open();

com = new SqlCommand();

com.Connection = con;

com.CommandType = CommandType.Text;

com.CommandText = "SELECT UserName, IsNever, CreateDate, ValidDays, ExpireDate FROM Users WHERE (UserID = @UserID) AND (UserPassWord = @UserPassWord)";

com.Parameters.Add("@UserID", SqlDbType.NVarChar, 30).Value = UserID.ToString().Trim();

com.Parameters.Add("@UserPassWord", SqlDbType.NVarChar, 60).Value = PassWord.ToString().Trim();

reader = com.ExecuteReader();

while (reader.Read())

{

objClsUsers = new ClsUserLoging();

objClsUsers.UserName = reader.GetString(0).ToString();

objClsUsers.Never = reader.GetBoolean(1);

objClsUsers.CreateDate = reader.GetDateTime(2);

objClsUsers.ValidDays = (short)reader.GetInt32(3);

objClsUsers.ExpireDate = reader.GetDateTime(4);

}

reader.Close();

com.Parameters.Clear();

}

catch (Exception ex)

{

objClsUsers = null;

throw ex;

}

finally

{

if (com != null)

com.Dispose();

if (con != null)

con.Dispose();

com = null;

con = null;

}

return objClsUsers;

}

 

I am getting an error a network or instance related error occured and there is not issue with DB and connection string because i am using another web application accessing the same db using web.config please assist