" wrote:

Jerry: Does that mean that Excel 2000 and below doesn't modify files?

No, that means that I observed it taking 97 & 2000 files to XP. I just
tested opening a 2000 file that was last saved by the same version of 2000.
As Saruman indicated, the name (Tools|Options|General|User name) of the last
person to open the file gets written to the file automatically. Even if the
file is opened by the person who last opened it, some bytes get changed. My
guess is that they record the date/time that the file was last accessed, but
I do not have immediate access to documentation for the file format to
verify. A further guess is that all versions have probably done this. I do
not know if it can be turned off, other than by making the file read only.

Jerry