This relates to Excel 2007 and seems to have started maybe about a week or so
ago. I never had this problem before. It is a nuisance and frustrating to
have to click on "No" in the dialog box when I simply want to exit Excel. It
now happens whenever I have first launched Excel 2007 (a process that
automatically generates a blank, new workbook titled "Book1") and then have
opened a preexisting workbook, or when I have started Excel by clicking on a
preexisting workbook, then opened a "New" workbook (which is titled "Book1"),
saved and closed any and all workbooks other than the new "Book1" (which I
have not used at all), and then try to exit Excel. It may be noteworthy that
this does not happen if I simply start Excel by clicking on a preexisting
workbook and then exit Excel without having made any changes to that
workbook. It seems to occur only when "Book1" (or, I suppose, a "Book2,"
etc.) is involved.