zdnet[.]com/article/new-windows-10-bug-hits-home-working-outlook-o365-teams-cant-access-internet/
docs.microsoft[.]com/en-us/windows/release-information/status-windows-10-1903#406msgdesc
Devices using a manual or auto-configured proxy, especially with a virtual private network (VPN), might show limited or no internet connection status in the Network Connectivity Status Indicator (NCSI) in the notification area. This might happen when connected or disconnected to a VPN or after changing state between the two. Devices with this issue, might also have issues reaching the internet using applications that use WinHTTP or WinInet. Examples of apps that might be affected on devices in this state are as follows but not limited to Microsoft Teams, Microsoft Office, Office365, Outlook, Internet Explorer 11, and some version of Microsoft Edge.
We are working on a resolution and are targeting a Microsoft Catalog only release of an out-of-band update to resolve this issue by early April.
Note: Be extra careful online & re: emails. Loads of people are now working from home, while lots of businesses have just setup the remote access making that possible. Mistakes setting up remote access & say a home office to work remotely are probably likely. Criminals know this, and being just as leery of catching the novel corona virus as everyone else, many probably want to work from home too. That makes home users and their networks a more attractive target.