Thanks. A registry search on the two machines showed that there were several differences and there was a lot of Word stuff not registered. The "registry server" program did not accept the winword.exe input as suggested but I did discover an (undocumented) "startup switch" for Word.
Entering "winword /r" in the "DOS prompt" (aka Run) window rebuilt the needed registry entries. The description of this switch says that it "Starts Word, starts Setup, makes changes in the Windows registry, and then quits. This switch forces a re-register of Word in the Windows registry."
My programs are working again. :-)