Why does the supposedly-saved file not really get saved?

Question

The following code is taken from this tutorial to create and save an Excel file with C#:

using Excel = Microsoft.Office.Interop.Excel;

namespace WindowsFormsAppExcelTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void buttonCreateExcelFile_Click(object sender, EventArgs e)
        {
            Excel.Application xlApp;
            Excel.Workbook xlWorkBook;
            Excel.Worksheet xlWorkSheet;
            object misValue = System.Reflection.Missing.Value;
            xlApp = new Excel.Application();
            xlWorkBook = xlApp.Workbooks.Add(misValue);
            xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1);
            xlWorkSheet.Cells[1, 1] = "http://csharp.net-informations.com";
            xlWorkBook.SaveAs("csharp-Excel.xls",
                Excel.XlFileFormat.xlWorkbookNormal, misValue, misValue, misValue, misValue,
                Excel.XlSaveAsAccessMode.xlExclusive, misValue, misValue, misValue, misValue, misValue);
            xlWorkBook.Close(true, misValue, misValue);
            xlApp.Quit(); 
            releaseObject(xlWorkSheet);
            releaseObject(xlWorkBook);
            releaseObject(xlApp);
            MessageBox.Show("Excel file created , you can find the file c:\\csharp-Excel.xls"); 
        }

        private void releaseObject(object obj)
        {
            try
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(obj); obj = null;
            }
            catch (Exception ex)
            {
                obj = null;
                MessageBox.Show("Exception Occured while releasing object " + ex.ToString());
            }
            finally
            {
                GC.Collect();
            }
        } 
    } // class
} // namespace

It seems to run fine -- I see the MessageBox msg, and I can step through it with no signs of problems. But the file does not get saved to the hard drive, as it should. Why not?

What does the message say? Where are you trying to save? Windows default settings will prevent you from saving to the root of C unless your running Visual Studio as Administrator. — Tyler Jennings, Oct 27 '15 at 17:39
It's all in the code; the message is "Excel file created , you can find the file c:\\csharp-Excel.xls"; it's saving it to root, since no folder is given in the SaveAs() call. It should be, anyway, unless I'm missing something. — B. Clay Shannon-B. Crow Raven, Oct 27 '15 at 17:43
I misunderstood, I thought the messagebox in the catch was displaying. Try right-clicking on Visual Studio and say Run As Administrator and see if that helps. Or specify a path such as your desktop. — Tyler Jennings, Oct 27 '15 at 17:46

B. Clay Shannon-B. Crow Raven · Accepted Answer · 2015-10-28T14:38:03.337

Saving to a specific non-root location (a subfolder) works, e.g. this:

String savefullpath = @"C:\misc\csharpExcelTest.xls";
    xlWorkBook.SaveAs(savefullpath,
        Excel.XlFileFormat.xlWorkbookNormal, misValue, misValue, misValue, misValue,
        Excel.XlSaveAsAccessMode.xlExclusive, misValue, misValue, misValue, misValue, misValue);

The file is indeed saved to that spot.

Apparently the only problem was trying to save to C/root. Even attempting to explicitly save to root, like this:

String savefullpath = @"C:\csharpExcelTest.xls";

...(as opposed to by simply providing a bare filename) fails ignominiously, telling me:

System.Runtime.InteropServices.COMException was unhandled
  HelpLink=C:\Program Files (x86)\Microsoft Office\Office12\1033\XLMAIN11.CHM
  HResult=-2146827284
  Message=Microsoft Office Excel cannot access the file 'C:'. There are several possible reasons:

• The file name or path does not exist.
• The file is being used by another program.
• The workbook you are trying to save has the same name as a currently open workbook.
    . . .

So: save to somewhere other than root to avoid this problem.

UPDATE

Also, it seems that it was being saved to my "Documents library" when I was not providing a folder/full path, and assuming it would save it to C:. I just happened to look into that folder this morning, and saw the file there.

Why does the supposedly-saved file not really get saved?

1 Answers1

UPDATE