Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello Greg,
Welcome to Microsoft Community and appreciate your time taken for sharing detailed information. I understand that Office 365 Previous version installation error. I could share with you some of my thoughts on this issue.
Office365 now supports the minimum operating system for Windows 8.1, so configuration can go wrong. If you're going to install it, you may need to upgrade your operating system. If you install Office 365 on Winodws 7, you may need to contact Microsoft Online Support to see if there is a way, but generally not.
Feel free to post back if you need any further assistance.
Best Regard,
Kevin | Microsoft Community Support Specialist
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