Hello there, this is Suganya. I'm happy to assist you.
It sounds like the issue with the user not being able to upload files in Teams chats may be related to the change in their SAM account name locally. This can sometimes cause issues with permissions and access to resources.
You can try the following troubleshooting steps to resolve the issue:
- Ensure that the user has the necessary permissions to upload files in Teams. You can check this by going to the Microsoft Teams admin center and checking the user's roles and permissions.
Manage teams in the Microsoft Teams admin center: https://learn.microsoft.com/en-us/microsoftteam...
- Sometimes resetting the user's password can help resolve authentication issues that may be causing the problem.
Change your Microsoft account password: https://support.microsoft.com/en-us/account-bil...
- Teams uses SharePoint Online to store files shared in chats, so it's possible that there may be an issue with the user's SharePoint Online permissions. Check the user's permissions in SharePoint Online to make sure they have the necessary access.
I hope this helps you to resolve the issue. Please let me know if you need further assistance. Thank you!
Regards
Suganya