If your old version of Office is already installed and working correctly then you usually won't need the CD available to install an
Office 2007 upgrade, but if at a later date you wanted to install it, you would want the CDs to be able to 'show' the Office 2007
installer that you had a product that qualified you for the upgrade (i.e. an upgrade doesn't increase the number of licenses you
have for Office, the upgrade is a part of the original for licensing).
Depending on the product suite you have in Office 2000 or Office XP(2002) your version of Office may have had additional programs no
longer included in Office 2007, in which case Office upgrades generally only remove products that they can replace, so your 'other'
old versions would remain intact unless you choose a custom installation when starting Office 2007 and telling Office 2007 to remove
the older versions of all Office products.
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I won't need my old software will I? And it upgrades all products in office,
correct? >>
--
Bob Buckland ?

MS Office System Products MVP
*Courtesy is not expensive and can pay big dividends*