A Microsoft file hosting and synchronization service.
I think you're right Allan. Laptop has been OK for a week (but it's not used every day).
Just now my desktop had the same problem. Identical symptoms - and it can't be Norton WiFi... because it's not installed and it's wired.
So... two separate PCs completely separate hardware, but both running W10 and Office 365. Same symptoms. This must be a M$ problem.... I'm not sure trying to clean both my machines up is really going to help....
Any other good ideas out there?
Mike