Can't open former Visio files with the same version of Visio

I have « Visio 2000 enterprise edition » and I could install it fine on my
DELL computer Inspiron 9300 in 2006. After the collapse of my hard disk, I
have put a new one on my Inspiron 9300 and set up again Windows XP SP2. I
then installed some recommended drivers from the DELL site.
The former files created with Visio are recognized according to the look of
the icons, but they can't be opened and a window displays the message that
« Visio is not compatible with this version of Windows (error 114) ». There
is an option « continue ». When I select it, a new window appear: « An error
has occured during the opération « Open a file ». This file cannnot be opened
because it was created with a recent or unknown version of Visio ». However,
« New Visio pattern » is listed in « All programs » and the corresponding
diagrams can be opened. Could you please tell me how to fix this impediment ?