How to suppress the file corrupt warning at Excel download?

Question

I have a web page which links to an Excel 2007 worksheet. It is a .xls file and not .xlsx file. When I click on the link I get the usual dialog box

Answer 1

I had same kind of issue and client complaining about it. I had done much googling but no luck. Finally I have created spreadsheet using cfspreadsheet, I know it require additional work than directly creating through HTML but it remove warning.