I have an excel 97 file that was mistakenly opened and saved in xl2002. No changes were done to the file, it just ran the save command.

Now when I open it in 97, on each save I get a box saying it was saved in another version of excel and asking if I want to lose my changes, etcs.. How do I tell Excel that this is an Excel 97 file again and not an Excel 02 file?