New Teams account shows as “Unknown user” in chat

Soorya B Shetty 5 Reputation points
2026-04-14T10:54:37.01+00:00

I created a new Microsoft account using my @companyname.in email (personal account, not work/school). I logged into Microsoft Teams and sent a message to a friend.

But on their side, it shows “Unknown user (invalid.teams.ms)” and they cannot accept or reply.

Why is this happening and how can I fix it?

Microsoft Teams | Microsoft Teams Free | Chats
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  1. AI answer

    2026-04-14T10:54:48.3266667+00:00

    The behavior occurs because the chat is between a personal Microsoft account and an organization (work/school) account, and the organization’s policies and Teams limitations affect how the personal user appears.

    When chats are created between personal accounts and organization members in Microsoft Teams Free, organizations can:

    • Restrict or disable chats with personal users.
    • Enforce data retention or removal of personal users from organization chats.
    • Cause certain users to display as Unknown or Anonymous.

    In such cases, the organization member may see the sender as Unknown user and be unable to accept or reply, even though the personal account can send the initial message.

    To fix or work around this:

    1. The friend’s organization admin must allow chats with personal users in their Teams/organization settings. If this is disabled or restricted, the personal account will continue to appear as Unknown/invalid and replies will be blocked.
    2. If organizational policy cannot be changed, use another method to communicate (for example, both users using personal accounts in Teams Free, or the friend inviting the personal account to a meeting where they can join as an anonymous guest).

    This is expected behavior when organizational policies limit interaction with personal accounts.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

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  2. Sumit D - IA 171.8K Reputation points Independent Advisor
    2026-04-14T11:40:19.7166667+00:00

    Hi Soorya,

    The name propagation takes 24 hours typically.

    After 24 hours,

    1. Sign out of your Microsoft Teams desktop app.
    2. Fully close Teams: right-click the Teams icon in the system tray and select Quit.
    3. Open File Explorer → paste %appdata%\Microsoft\Teams in the address bar → press Enter.
    4. Delete all contents inside the Teams folder.
    5. Launch Microsoft Teams again and sign back in.

    I hope this information helps. If you have any more questions, don't hesitate to reach out.

    Otherwise, please take a moment to rate the answer. Wishing you good luck!

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