A family of Microsoft word processing software products for creating web, email, and print documents.
I contacted MS support, and the agent resolved the problem. The solution was to download o15-ctrremove.diagcab, which is an Office uninstaller application. I gave Agent remote access to my computer, I watched action go by rather fast, but once that uninstaller tool was used, the agent deleted any residual Office folders (i.e. Word, Excel, Powerpoint) from Program Files. I had to reboot, then the agent reinstalled Office using the Setup.exe from my account page. It all works now.
Some lessons learned:
- Something went wrong early on with my attempts to Uninstall/Repair Office. Not sure what did it (whether it was Control Panel method, or online Uninstall tool), but something removed Office from my installed application list, but didn't remove perhaps registry settings or something that left my computer in this limbo of not being able to completely remove a corrupt Office install, and not being able to reinstall either. Perhaps this was an artifact of the corrupt install.
- Now that everything is working again, I checked the AppvIsvSubsystems64.dll at this location: C:\Program Files\Microsoft Office\root\Office16. The File Type is .simlink, which means it should not contain any data. I misunderstood that earlier.
- While Office applications are working again, the Edge browser is still very unstable - perhaps even more so. When I try to type something into the search bar, it crashes. So that will be the next problem for me to solve.
I consider this problem resolved. Thanks to all those who tried to help.