It was sent by a you were expecting a video from. You have scanned it with VirusTotal if you found it online. Upload YouTube videos - Android - Google Help
Use the YouTube Studio app * Open the YouTube Studio app . * At the top, tap Create . * Select the file that you'd like to upload. Google Help Upload YouTube videos - Android - Google Help VID-222vvuh(1).mp4
If you see an error like "Format not supported" or "File corrupted": It was sent by a you were expecting a video from
You can often drag and drop the .mp4 file directly into a Chrome or Safari tab to play it instantly. VID-222vvuh(1).mp4