A family of Microsoft word processing software products for creating web, email, and print documents.
My assumption that the problem was caused by Microsoft and not related to the individual computer was correct.
Updates were continuing to be installed on my “Office Home and Student” without my knowledge and the latest update was dated the very day my programs were disabled.
Thanks to the assistance of everyone who responded to my Forum request, and especially: Hojjat Bohlooli who supplied the instructions for removing the offending update, both my XP computers are now up and running my Office 2010 programs properly.
As a conclusion to this matter, and to assist others who have been damaged by this problem, here is the remedial process as provided by Hojjat Bohlooli:
Uninstall recently installed update of office 2010 named KB4461522. This update breaks compatibility of office 2010 on windows XP.
· Open 'Add or Remove programs' from Control Panel
· Select the “show updates” on the top of window
· Find Update, KB4461522 dated 14 Nov 18 for Office 2010 in the list and remove it.
Reboot computer