Excel automation errors from C#

Hi guys,

This is my first post, and I'll try to make myself clear.
I'm trying to launch a macro from a c# program using the following code:

//////////////////

object oMissing = System.Reflection.Missing.Value;
Microsoft.Office.Interop.Excel.ApplicationClass oExcel = null;
Microsoft.Office.Interop.Excel.Workbooks oBooks = null;
Microsoft.Office.Interop.Excel._Workbook oBook = null;

oExcel = new Microsoft.Office.Interop.Excel.ApplicationClass();
System.Threading.Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo("en-US");

oExcel.Visible = true;

oBooks = oExcel.Workbooks;

oBook = oBooks.Open(path, false, false,
oMissing, oMissing, oMissing, oMissing, oMissing, oMissing,
oMissing, oMissing, oMissing, oMissing, oMissing, oMissing);


this.RunMacro(oExcel, new Object[] { "IPReviewPerformStep", stepIndex.ToString(), settings.SAPAPOUserName, settings.SAPAPOPassworde });

///////////////// Method to run a macro

private void RunMacro(object oApp, object[] oRunArgs)
{
oApp.GetType().InvokeMember("Run",
System.Reflection.BindingFlags.Default |
System.Reflection.BindingFlags.InvokeMethod,
null, oApp, oRunArgs);
}



////////////////////////

So far, I get the following behaviour: The excel file is opened successfully, the macro is launched, but I get automation errors on basic VBA objects like "Application" or "ThisWorkbook" (see error window in attachment).
However, when I launch the macro from the excel file manually, it works!
Moreover, I have a similar program launching a macro in another excel file and it works.
Is it possible that my excel file is corrupted?

If you have any idea, feel free to help! Thanks

Is it possible that my excel file was made in a too old version of excel? maybe excel 7.0

Still can't go any further in that project...

I found out that the max number of arguments when invoking the runmacro method is 10. If you try put more than 10 args, you'll get the same error as mine.