Based on your detailed case description, we completely understand the situation and your feelings.
It is recommended that you try the following steps to check the solution:
- Please try to compress the file when uploading it. For example, there is a size limit of 15GB per file for files uploaded to Teams chat.
- Slow or unstable Internet connections can sometimes cause uploads to fail. Before attempting to upload files, please make sure you have a stable and reliable internet connection.
- Please try to clear the Teams cache and upload the file again.
- If you have ruled out all of the above issues, run the following test to diagnose: Run Test: Unable to upload file to Teams chat.
You can also report your problems in the Teams client here. Thanks for your understanding and support.
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