What you need to know
- The latest cumulative update for Windows 10 version 1909 causes issues for Microsoft Teams, Outlook, and OneDrive for Business.
- The issues appear to affect a small subset of people's systems.
- Microsoft suggests rebooting your system as a workaround as it investigates the issue.
Those that are affected by the issue will see a message that states, "We ran into a problem. Reconnecting..." or something similar. The message also has a button to restart the app. The error code for the message is 800800300.
Microsoft sent out a message through Microsoft 365 advisory regarding the issue (via Bleeping Computer):
We've received reports that some users on Windows Update KB 5003169 are unable to connect to various Microsoft 365 desktop clients including Microsoft Teams, Outlook, and OneDrive for Business. Our investigation has determined that a code issue exposed by a recently deployed Windows update, detailed in KB 5003169, is causing the problem.
The temporary fix for the issue is to restart your PC. Alternatively, Microsoft suggests that you use the web versions of Teams, OneDrive for Business, and Outlook while it investigates the issue. Using a web version of a service won't deliver the same experience, but it will allow people to access the popular Microsoft services until a more permanent solution is found.
Windows 10 version 1909 is now officially out of support for standard users, though it's probably safe to assume that Microsoft will find a way to have its most popular services work on it.
