I have a MS Excel 2003 file that has xml in it but a .xls file extension.
When I open it up in MS Excel 2003 it opens with no problem.
However, if I open the file in MS Excel 2007 it first shows a dialog mentioning the file is in a different format then specified by the file extension. Is there a way to avoid getting that dialog in 2007 since 2003 never displayed the dialog?

Also, I noticed that if I change the file extension to .xml it opens in MS Excel 2007 with no dialog. However, we prefer to keep the file extension as .xls.

Thanks,

Patrick