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We have already documented that this is not possible:

This feature does NOT support the unrelated, but confusingly similarly named, OneDrive for Business product by Microsoft which you typically get access to as part of an organization-level Microsoft Office 365 for Business subscription. Please note that the regular (not "for Business") Microsoft Office 365 subscription gives you access to the regular OneDrive product which is compatible with our software as explained above.

As for the authentication part, I have already explained why it is not possible. TL;DR: https://github.com/OneDrive/onedrive-api-docs/issues/119 You need to create a new application per Business subscription. This means that you would
EITHER need to pay us to maintain and provide you with a custom version of Akeeba Backup with a custom OneDrive for Business integration and maintain the server-side portion of it (thousands of Euros per year since we have to set up a parallel product line just for you)
OR have you register your own app, configure and host the server-side connector (you get to figure out Microsoft's confusing admin pages on your own - good luck with that)

Probably there is, indeed, a simpler / better way to do it. However, if it does, it's not documented. If it's not documented it's as good as not existing. The link I gave you above is from Microsoft's OneDrive API project on GitHub. The Microsoft employee admits that their documentation is lacking. Two years later, the documentation has NOT improved. So now please tell me exactly how you " know for a fact that Microsoft is very willing to help developers that want to embed there software" when they DO admit their documentation sucks and do nothing to fix it for two years? The evidence I have, on their official repository, seems to directly contradict your assertion.

I have said it before, I will say it again. If anyone can provide me with documentation on how to do that that does not require registering a new application per Business installation I have absolutely no problem whatsoever writing the code. Merely asserting something that contradicts objective reality from a safe position doesn't help either of us. Give me docs!