>You mean i need .net interop DLLs. But i open it , i saw two Microsoft.Office.Interop.Excel version 11 or 12.
>After i add the Microsoft.Office.Interop.Excel version 12. and run program .
>
>In this code, Sheet.Range("C" & iRow).Value = "AAA" will error.
>
>COMException was unhandled
>HRESULT: 0x80020011 (DISP_E_NOTACOLLECTION))

I think Range() requires two parameters. See: http://msdn.microsoft.com/en-us/library/microsoft.office.tools.excel.worksheet.range(v=vs.80).aspx