Will Outlook.com Calendar Sync ever work reliably

It does not help. Still not working.
I got this answer from customer support:

> Currently, there isn’t a workaround available for this behavior. The issue is planned to be addressed in the upcoming version 11.

I wonder when this version 11 is available…

That sounds like then with the change to MS Graph as per @Michal_Burger advised below should then hopefully resolve these issues you and others are experiencing in this thread.

For me personally using the latest V10.4.5326 PC or Mac i have no current AirSync issues with my own Live, Hotmail or Outlook accounts as far as Mail, Calendar, Contacts or Tasks go, so i suspect its possibly either eg: Microsoft Server issues randomly happening on some mirror servers around the globe, or some other external unknown factors causing these ongoing issues.