title: error "Login failed for user" C# with SQLConnection
body: <p>I created a database (without user or password) as a service-based database.</p>
  
  <p>Now I'm trying to insert to a database, but there is a error "Login failed for user"</p>
  
  <p>I have this code:</p>
  
  <pre><code>string J_connetionString1 = null;
  SqlConnection J_connection1;
  SqlDataAdapter J_adapter1 = new SqlDataAdapter();
  string J_sql1 = null;
  J_connetionString1 = @"Data Source=.\SQLEXPRESS;Initial Catalog=J_InsData";
  
  J_connection1 = new SqlConnection(J_connetionString1);
  J_sql1 = "update instinfo set instinfoNAME = textBox2.text where instinfoID ='1'";
  try
  {
      J_connection1.Open();
      J_adapter1.UpdateCommand = J_connection1.CreateCommand();
      J_adapter1.UpdateCommand.CommandText = J_sql1;
      J_adapter1.UpdateCommand.ExecuteNonQuery();
      MessageBox.Show("Row updated !! ");
  }
  catch (Exception ex)
  {
      MessageBox.Show(ex.ToString());
  }
  </code></pre>
  
  <p>i can't comment so i edited the Q.</p>
  
  <p>this error appeared by using this code</p>
  
  <p>error :
  system.Data.sqlclint.sqlexpection(0x80131904)
  cannot open database "J_InsData" request by the login. the login faild
  login failed for user J-PC\J</p>
  
  <p>code:
   J_connetionString1 = @"Data Source=.\SQLEXPRESS;Initial Catalog=J_InsData;Trusted_Connection=True;Integrated Security=SSPI";</p>