On Sat, 17 Oct 2009 23:06:11 -0700, Robert Baer
wrote:

Worked very nicely.
With one exception, "upgraded" programs create files that are
incompatible with older versions of the "same" program; it is rare that
a program allows one to create files fit for other versions, as well as
rare that the newer version even reads (some of the) olcer version files.

Excel 2007 does a fine job of making backward compatible, as well as
co-compatible workbooks.

Also, if one makes a new, 2k7 file and attempts to open it with 2k3, it
will prompt you for the DL of the compatibility code so that 2k3 can open
2k7 files.