Hello John,

Yes that is the case. You cannot reference the later PIA because these contain
new functionality not yet available when the previous version came out. But
the old excel functions are still built into the new executables, so the
older PIA will work regardless of later upgrades. Until MS decides to deprecate
such functions in later versions

Knowing that we'll have a 64 bit version of the next Office, I guess that
there will be a break in backwards compatibility as I doubt that a 32 bit
PIA for Excel 2003 would be able to load Excel 2010 64 bit. It should still
work with the 32 bit version though. (not verified nor tested)

Jesse

OK, you are saying that if my program references the Office 2003 PIA
(Microsoft Excel 11.0 Object Library) this will work with later
versions of Excel, but not the reverse. This is actually the opposite
of what I would have expected. Any idea what is going on here? And
is this likely to hold when Office 2010 comes out.

In article ,
Andreas Johansson wrote:

Usually it is most easy to install the earliest version of excel you
want to use on the development machine. Then reference that version
instead in your project.

You might be able to install them side by side so no need to
uninstall 2007.

--
Jesse Houwing
jesse.houwing at sogeti.nl