Hi again, Simon.
Unfortunately, Office 2007 appears to use a different file format than previous version - for example, docx or something like that in Word 2007. Therefore, if someone sent me an email with a 2007 Word attachment, I couldn't open it in 2003. I believe that Microshaft put out a workaround that enables 2007 files to be read in previous versions of Office, but you can't edit them, which is no good to me.