Hi, the short answer is no. Assuming you want to email someone a .mp4 video file and that the video file was small enough (in data size) to be emailed, then there is nothing to stop them playing it more than once or copying it etc. If you simply want to send someone a sample of something you can create, then either send it at a very low resolution, or include a water mark on the video. For example PhotoVidShow will generate a water mark on any slideshow it creates on non paid (registered) versions of the software. To have a system of only being able to play once etc, you would need to email a link to your own website and have restricted playback system running on your own website.