Hi @bmon ,
According to your description, I successfully installed Office 365 on my windows 10 with your .xml file.
Could you provide a screenshot of detailed error message or describe it in detail?
> The normal Installer stays stuck in a loop forever, no error code, no nothing, just saying it's ready soon.
<<How did you install it with the “normal Installer”?
Please go to Control Panel\Programs\Programs and Features to check whether Microsoft 365 has been installed.
If yes, restart your PC and try to repair Office to check this issue.
If no, please uninstall all versions of Office by using the uninstall support tool in "Uninstall Office from a PC".
Then please try to download and run Microsoft Support and Recovery Assistant to help install Microsoft 365.
You could also refer to the article “Office 365 Click-to-Install fails” to update Win 8.1 to have a check.
Besides, please turn off the third-party software in your PC (if there is) temporarily to check the issue.
Hope the information is helpful to you. Any questions and updates, please let me know.
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