no i am not using any third party dll m opening my excel like this ApplicationClass xlApp = new ApplicationClass(); //xlApp.ShowStartupDialog = false; //xlApp.DisplayAlerts = false; Workbook xlWBook = xlApp.Workbooks.Open(sFileName, 0, false, 5, "", "", false, Excel.XlPlatform.xlWindows, "", true, false, 0, true, false, false); every thing working correctly but when i debug my code... n start downloading the data it gives popup as conneting to server to get informtaion... popup goes automatically.. but i want to hide tht