Turn off XML prompt when saving Excel 2003 document
 

How do I turn off this amazingly annoying Excel 2007 prompt when saving an
Excel 2003 spreadsheet?...I am forced to use Office 2007 at work, but use
Office 2003 at home and prefer it over anything Office 2007 has to offer?

This document is both encrypted and password protected. The office open xml
formats available in the 2007 release provide stronger encryption. Do you
want to increase the security of this document by converting it to an office
xml format?

Surely there is some kind of hack to do this, or some setting
somewhere...I've already gotten around the issues with Outlook in Office 2007
by going to Thunderbird...

If I can't find a solution then my next option is to go to Open Office...