Hi @Alexandre Gagné ,
Did you changed any settings on Teams Admin Center?
And how many users were in trouble? Do these users have anything in common?
Some general ways to fix this are:
- Re-install the teams app.
- Check the permissions of their phones to attach photos or other files.
- Try using another network to login Teams.
Please try uploading these files from the Teams for browsers in your mobile devices.
Best regards,
Lou
If the response is helpful, please click "Accept Answer" and upvote it.
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.