Here's my code which does nothing. Generates no error, but doesn't copy the
sheet into the workbook. It does successfully rename the "Operations" sheet,
but is supposed to copy a sheet into the workbook in front of that one.

private void CopyTab(excel.Worksheet ws, excel.Workbook wb)
{
try
{
foreach (excel.Worksheet w in wb.Sheets)
{
if (w.Name.IndexOf("Operations") -1)
{
w.Copy(ws, Type.Missing); // copy ws into wb workbook
// gets no error, but doesn't do anything else either!
w.Name = "Operations (updated)";
break;
}
} // end foreach
}