If the video won't play, it might be an incomplete download . Try going back to the original Telegram message and clicking the "download" icon again until the circle fills completely.
If you found this file in a folder and don't remember downloading it, be cautious. While .mp4 files are generally safe, always ensure your antivirus is active before opening files from unknown Telegram groups. 1_4992273507296477755(1).mp4
The (1) at the end indicates that you have downloaded this exact file twice, and your operating system renamed the second copy to avoid overwriting the first. 2. How to Open the File If the video won't play, it might be an incomplete download