I'm not trying to be coy, just showing how easy it is to find stuff in the reg. Not sure about the key name however. It may vary depending if the M$ Office builds are all from the same source. If some are from shrinkwrap or OEM bundled builds, the ProdID may vary.

You may have to enumerate the various keys looking first for the 'DisplayName' before manipulating 'InstallSource'.

Remember as well as the two CDs would have separate entries.
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