A Microsoft file hosting and synchronization service.
29 June:
Hi,David
We are really sorry for the inconvenience caused to your life and work, and we are equally hopeful that your issue is resolved and we are waiting for an update on the issue!
Microsoft's development team will resolve this issue as soon as possible, thank you for your time and effort!
Best Regards, Maxine | Microsoft Community Support Specialist
23 July: Still broken. In fact, it's now broken even worse than before.
https://1drv.ms/f/c/c8069a075af993a8/EgoQPfFHRohLi3iFywCM_gsBSAndxY3jGiCFwpdtcfnC4w