Building and customizing solutions using Microsoft 365 Copilot APIs and tools
Hello Robbie Kohart
Thank you for reaching out and informed us about your concern.
According to this article here: File formats supported by Microsoft Copilot and File upload in Microsoft Copilot unfortunately mp4. file is currently not supported.
If you would like to request support for MP4 uploads or report the issue directly to the product team, I'd recommend submitting feedback through the Feedback Hub or the in-product Copilot feedback option. Feedback submitted through these channels is reviewed by the appropriate teams and helps inform future improvements.
Thank you for your understanding.