A Microsoft file hosting and synchronization service.
Ok, just got off the phone with Apple and this is the situation. The issue is (rather obviously) surrounding permissions. It appears that BOTH Apple and Microsoft made changes in the nitty gritty details (which haven’t been shared with me) regarding how iOS authenticates write permissions to OneDrive. Google, for example, have not made changes and so it still works but there’s every possibility that they may make the same changes if the changes are rooted in security.
Apple’s stance is that they want their devices to be as secure as possible and, as such, they are currently unwilling to reverse the changes that they made. So, we are reliant on MS to get the feedback and, essentially, make changes in order to play ball with Apple.
The best thing to do is to take this information and share it with as many people as possible and encourage them to make individual support calls to both companies until one of them gets enough that they are willing to back down. That being said, if it is a security issue and Apple are right, then the onus really is on MS to modify OneDrive authentication to align with the requirements that Apple now set for OneDrive (and all cloud services) to work with iOS devices.
Until then, work around are necessary but everything is possible, if in more roundabout ways, and ‘sharing’ on iOS devices and selecting OneDrive does work.
Go onto your social media and share this information and what needs to be done!
If someone from MS is monitoring this thread, please reach out to me as we need to make this an official support issue with MS.