无法访问对象Excel WorkBook ASP.NET的属性“ saveAs”

Question

I have a little issue here: I have an asp.net application built in C# and it generates an Excel pivot table. I have no problem when I run it on localhost with IIS Express from Visual Studio, it creates the file from a datasource and downloads it to my downloads folder with no problem.

But once I put it on my production with IIS Server and try to test the application, when I click the export button, I get the following exception:

Description: unhandled exception when executing the current Web request. Review the stack trace for more information about the error and where it originated in the code.

Exception: System.Runtime.InteropServices.COMException: Cannot obtain acces to the SaveAs property of the Workbook class.

Source code error:

Unhandled exception when executing the current Web request. Review the stack trace for more information about the error and where it originated in the code.

Pool tracking:

[COMException (0x800a03ec): Cannot obtain access to the SaveAs property of Workbook class.]
System.Dynamic.ComRuntimeHelpers.CheckThrowException(Int32 hresult, ExcepInfo& excepInfo, UInt32 argErr, String message) +145
CallSite.Target(Closure , CallSite , ComObject , String ) +702
System.Dynamic.UpdateDelegates.UpdateAndExecute2(CallSite site, T0 arg0, T1 arg1) +491
System.Dynamic.UpdateDelegates.UpdateAndExecuteVoid2(CallSite site, T0 arg0, T1 arg1) +657
inicio.pivotTable(DataTable source) +11550
inicio.btnExportar_Click(Object sender, EventArgs e) +153
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +11773973
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +150
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5062

This only happens when I run it from IIS Server.

Here is the code I use for generating my Excel file:

private void pivotTable(DataTable source) {
    System.Globalization.CultureInfo oldCulture = System.Threading.Thread.CurrentThread.CurrentCulture;
    System.Threading.Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo("en-us");

    //get the type of excel application
    Type ExcelType = Type.GetTypeFromProgID("Excel.Application");
    dynamic xlApp = Activator.CreateInstance(ExcelType);

    dynamic xlWBook = xlApp.WorkBooks.Add();

    DataTable dt = source;

    int x = dt.Rows.Count;
    int y = (dt.Columns.Count);
    int col, row;

    Object[,] rawData = new Object[x + 1, y];

    //filling data
    for (col = 0; col < y; col++) {
        rawData[0, col] = dt.Columns[col].ColumnName.ToUpper();
    }

    for (col = 0; col < y; col++) {
        for (row = 0; row < x; row++) {
            rawData[row + 1, col] = dt.Rows[row].ItemArray[col];
        }
    }

    // Excel worksheet
    dynamic xlWSheet;
    String uRange = string.Format("A1:{0}{1}", excelColName(dt.Columns.Count), dt.Rows.Count + 1);

    xlWSheet = xlWBook.WorkSheets.Add();
    xlWSheet.name = dt.TableName;
    //rawData as exactly as the datasource
    xlWSheet.Range(uRange, Type.Missing).Value2 = rawData;

    dynamic dataRange = xlWSheet.Range(uRange);

    xlWBook.Names.Add(Name: dt.TableName + "_Range", RefersTo: dataRange);

    xlWSheet = xlWBook.WorkSheets.Add();
    xlWSheet.name = "Pivot_" + dt.TableName;

    dynamic ptCache = xlWBook.PivotCaches.Add(SourceType: 1, SourceData: dt.TableName + "_Range");
    dynamic ptTable = ptCache.CreatePivotTable(TableDestination: xlWSheet.Range("A3"), TableName: "PT" + dt.TableName);

    //generating pivot table
    ptTable.ManualUpdate = true;
    ptTable.PivotFields("CLIENTE").Orientation = 3;
    ptTable.PivotFields("CLIENTE").Position = 1;
    ptTable.PivotFields("CLASE").Orientation = 1;
    ptTable.PivotFields("CLASE").Position = 1;
    ptTable.PivotFields("AÑO").Orientation = 2;
    ptTable.PivotFields("AÑO").Position = 1;

    ptTable.CalculatedFields().Add("MONTO", "=SUM(TOTAL)", true);
    ptTable.PivotFields("MONTO").Orientation = 4;
    ptTable.ManualUpdate = false;

    ptCache = null;
    ptTable = null;
    xlWSheet = null;
    dataRange = null;
    //get the path from webconfig
    string path = ConfigurationManager.AppSettings["path"];
    //check if the file is alredy in the path, just to avoid excel asking to replace it
    if (File.Exists(path + Session["usuario"].ToString().Replace(" ", string.Empty) + ".xlsx")) {
        File.Delete(path + Session["usuario"].ToString().Replace(" ", string.Empty) + ".xlsx");
    }

    //save the generated file in the path 
    //this is the method mentioned in the iis exception, but it says "property"
    xlWBook.SaveAs(path + Session["usuario"].ToString().Replace(" ", string.Empty) + ".xlsx");
    //quit excel
    xlWBook.Close();
    xlApp.Quit();
    xlWBook = null;
    xlApp = null;

    GC.Collect();
    FileStream fs = null;
    string FileName = "presupuesto" + Session["usuario"].ToString().Replace(" ", string.Empty) + ".xlsx";
    //get the file i saved before
    fs = System.IO.File.Open(path + Session["usuario"].ToString().Replace(" ", string.Empty) + ".xlsx", System.IO.FileMode.Open);               
    byte[] file = new byte[fs.Length];
    //read the file
    fs.Read(file, 0, Convert.ToInt32(fs.Length));
    fs.Close();
    //send the file in response
    Response.AddHeader("Content-disposition", "attachment; filename=" + FileName);
    //delete de file because i don't want it to be in server anymore
    System.IO.File.Delete(path + Session["usuario"].ToString().Replace(" ", string.Empty) + ".xlsx");
    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
    //send the file in response
    Response.BinaryWrite(file);
    Response.End();

    System.Threading.Thread.CurrentThread.CurrentCulture = oldCulture;
}

I don't know what to do, I'll be thankful for any help

Answer 1

Try to run the application using an Application Pool in IIS that uses the credentials of a Windows user on the server that can also be used to logon to the server. Office Automation does not work for users that cannot have an interactive Windows session.