User Impact: Users may be unable to launch the Microsoft Teams desktop client. More info: Affected users may see a message that states, “Loading Microsoft Teams”; however, the client does not load. Affected users may be able to load Microsoft Teams in compatibility mode as a workaround.
Alternatively, the Microsoft Teams web client works as expected. Users with the same email address for their work and personal account can rename their personal account by following the instructions described here: https://go.microsoft.com/fwlink/p/?LinkID=733247
Current status: At this time, additional testing and validation is required to ensure the fix fully mitigates the issue, while also ensuring it doesn’t introduce additional impact. Scope of impact: Impact is specific to users utilizing the same username with work/school accounts and their personal Microsoft account.
Preliminary root cause: A recently deployed update inadvertently introduced a code bug that causes authentication issues for a subset of users when accessing Microsoft Teams from the desktop client, resulting in impact.