Why don't my students' names appear in the chat box when I look them up?

Hi @Melina Culquilambert,

Welcome to the Microsoft Q&A forum.

Thank you for reaching out to us. I’d like to provide you with the following information:

I noticed that you tagged education, so I’ll share details relevant to an education account:

This issue occurs when:

1. Your account and the student’s account are not in the same tenant:
   • The two accounts belong to different tenants.
   • One of them is using a personal account.
2. The student’s Teams account might not have a license assigned.

Education accounts are set up and managed by the school’s administrator (often the school’s IT department). In this case, please contact your school’s IT department to help connect your current account with the student’s account. Provide them with the following steps to resolve the issue:

1. Check if your account and the student’s account are in the same tenant:

• Verify if the email domain of both accounts is the same, for example: @school-name.edu.onmicrosoft.com.
• If the email domains are different, ask the IT department to add your account as a guest user in the student’s tenant by following these steps:
  • Step 1: Go to https://admin.microsoft.com.
  • Step 2: Click Users > Guest users.
  • Step 3: Add your account to the student’s tenant under Guest users.

2. Check the Teams license for the student:

• Ask the IT department to assign a Teams license to the student so you can communicate more easily.

After the IT department completes these checks and configurations, clear the Teams cache using the steps below to see the student’s name in the recipient list:

1. Exit the Teams application completely.
2. Press Win + R to open the Run dialog.
3. Enter the following path and click OK:

%userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams

1. Delete all files and folders inside.
2. Restart Teams.

I hope this information is helpful. Please follow the steps above and let me know the result. If the issue persists, we can work together to find a solution.

Thank you for your patience and understanding. If you have any questions or need further assistance, please leave a comment on this post so I can continue to support you.

Looking forward to your response.

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". 

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread. 

If your students' names do not appear in the chat box when you try to send a message in Microsoft Teams, it could be due to a few reasons related to how Teams integrates with Microsoft Entra ID and the class roster management. Here are some potential causes:

1. Class Membership Issues: Sometimes, users may not appear correctly in their Class Teams even if they are listed in the corresponding Microsoft 365 group. This can happen if the Teams cache is not updated with the latest data from Microsoft Entra ID.
2. External Federated Contacts: If your students are considered external contacts or if there are issues with their accounts being recognized in Teams, they may not show up in the search results. Ensure that their accounts are properly set up and that you are searching by their email addresses rather than names.
3. Information Barriers: If your organization has implemented Information Barriers, it might restrict communication between certain groups of users, which could prevent you from seeing or messaging your students.

To troubleshoot this issue, you may want to check the class roster in Microsoft Entra ID, ensure that the Teams cache is updated, and verify if any Information Barriers are affecting communication.

References:

• Missing Teams Memberships or Access
• External federated contacts don't appear in Teams search
• Resolve communication issues in Information Barriers