Student can see and edit document, which is shared in teachers' chat.

Dear @Ernest Rajh

Welcome to the Microsoft Q&A Community! 

Thank you for contacting support. I understand that a student is listed with Edit permissions on a Word document that was intended to be shared only among teachers in a group chat.   Please provide the following information so I can identify the exact access path and tailor the resolution appropriately. 

1. Was the document created directly in Office on the web or uploaded from OneDrive or a local device? 
2. Was the file ever moved or copied to a SharePoint site, a Staff Team, a Class Team, or any shared document library? 
3. In the Manage access pane for the file, does the student appear under Direct access, via a Sharing link, or through a Microsoft 365 group or security group?  
4. In the Links section, is there a link configured as Anyone with the link or People in your organization with the link? If there is, kindly create a new link with the Specific people option and include only the intended teachers or a dedicated teacher‑only security group. 
5. Has anyone used the Share command from within Word to invite users by email? 
6. Do the document comments contain an at‑mention of the student, which can automatically grant access? 
7. Has any teacher forwarded or pasted a previously created sharing link outside the chat? 

 In the meantime, try applying the actions below to remove the student’s access and restrict sharing scope. These instructions assume the file resides in the owner’s OneDrive, which is the default storage for files shared in Teams chats. 

Remove unintended access   

• Open OneDrive for the file owner and navigate to My files, then Microsoft Teams Chat Files, and select the document 
• Open Manage access 
• Under Direct access, remove the student if listed 
• If the student appears via a Microsoft 365 group or security group, remove that group from this item or proceed to break inheritance as described below 

Address permissions inheritance where applicable   

• In Manage access, open Advanced to access the classic SharePoint permissions page 
• Select Stop inheriting permissions if available 
• Remove broad principals such as Everyone except external users and any student or class groups 

 Relocate the file if the current location is not staff‑only   

• If the file is located in a document library or site where students have Member permissions, move it to a staff‑only OneDrive folder or to a staff‑only SharePoint site with unique permissions 
• Re‑share the file using a Specific people link limited to the intended audience 

Contact the School's Admin 

Although the file owner can remove the student’s access directly, identifying how the access was granted and ensuring it does not happen again may require reviewing organization‑wide sharing settings, security group memberships, or default link policies. These areas can only be checked and adjusted by an IT admin through the Microsoft 365 and SharePoint admin centers. 

If needed, the IT administrator can also review audit logs to confirm who granted the access and when, and can update sharing governance to prevent similar issues in the future. 

In case the above steps don't work on your end or you need further instructions on reaching out to the admin, please provide answers to the scoping questions . Once received, I will supply precise, step‑by‑step instructions aligned to your configuration. I appreciate your cooperation, and I am here to assist you further. 

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