I am getting the following error warning when opening an .xls file generated using 'CarlosAg.ExcelXmlWriter.dll' in Excel 2007:
The file you are trying to open,
'', is in a different format than specified by the file extension. Verify that the file is not corrupted and is from a trusted source before opening the file. Do you want to open the file now?
Any ideas how I can resolve this?