Cannot add a specific user to an existing group chat in MS Teams

Question

Hi,

A user wants to add their new teammate to an already existing group chat in teams but they can't add him. They tried to add from both the desktop app and the web version and nothing seems to be working. Once the add option is selected, the user ID is found within teams and irrespective of what option is chosen ( don't include chat history, include chat history, or include chat history from past number of days) once the add button is selected there is no error but the person is not getting added. We tried to add him to a new chat and they have no issue adding him.
All the users are part of the same domain/company; no external users are involved. Also we can add the user to majority of the groups only few groups are behaving this way. I really appreciate any help you can provide.

Answer 1

Good day @Anish Devan,

Thank you for taking the time to describe the scenario in such detail. I really appreciate the clarity you provided, as it helps narrow things down significantly.

Based on what you have shared, it looks like you have already ruled out many of the common causes. Since the user can be added successfully to new chats and other group chats without any issue, this strongly suggests that the problem is unlikely to be related to licensing, client version differences between desktop and web, or basic user permissions.

When Teams allows you to find the user, proceed through the add flow, and select the chat history option without showing any error but still does not actually add the person, this behavior often points to a service‑side inconsistency. In some cases, the affected group chat itself may have experienced a backend synchronization issue that cannot be corrected through client troubleshooting alone.

As this is a user‑to‑user support forum, moderators and contributors here do not have access to Microsoft’s backend systems and are unable to directly investigate or repair chat‑level issues. When the behavior is isolated to only specific group chats like this, the most effective next step is to engage Microsoft Support so they can review the affected chat objects at the tenant level.

I would recommend raising a support request through the Microsoft 365 Admin Center. You can follow the guidance outlined in: Get support - Microsoft 365 admin | Microsoft Learn. If you are an end user without admin access, it would be best to work with your organization’s IT administrator to open the ticket on your behalf.

Tips: You can switch off the Support Assistant as shown in the screenshot, then type a few short characters into the search box and select Get Help. After that, wait for the Contact Support button to appear and click it. When you reach the contact‑method step, I recommend choosing Email, as it tends to be a more consistent and effective option in my experience. At the final step, be sure to clearly describe your request in the description fields so the support engineers can quickly understand your issue and assist you more effectively.

Once the support ticket is opened, a technical support engineer can review the backend configuration, perform deeper checks, and if needed, run the appropriate synchronization or repair processes. This is typically the fastest and most reliable way to resolve issues of this nature.

Thank you again for reaching out. I sincerely hope the higher‑level investigation teams will be able to help resolve this issue and ensure everything runs smoothly for you moving forward.

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Answer 2

In this scenario all users are internal, the user can be added to new group chats and to most existing group chats, but adding them to a specific existing group chat silently fails (no error, user not added).

From the provided context, the closest documented cause for a similar “can’t add member” behavior in Teams is a directory permission setting in Microsoft Entra ID (Azure AD):

• If the UsersPermissionToReadOtherUsersEnabled setting is False, adding members in Teams can fail even though adding them to Microsoft 365 groups works.

Action for the Microsoft 365/Azure AD admin:

1. Go to Microsoft Entra ID (Azure AD) in the Azure portal.
2. Locate the UsersPermissionToReadOtherUsersEnabled setting.
3. If it is set to False, change it to True.
4. After the change propagates, try adding the user again to the problematic group chat.

This setting controls whether users can read other users’ information in the directory; when disabled, Teams membership operations can fail in specific scenarios without giving a clear error in the client.

If the setting is already True and the issue persists only for a few specific chats, the next step is to escalate via Microsoft support, as the behavior is not further detailed in the provided documentation.

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References:

• Error "We couldn't add member" when adding users to Teams