If your Tactacam videos are not playing correctly or showing up in your media player, as long as you have the correct type of SD card inserted it is likely then due to the media player you are using to watch footage back on. Not all media players are the same and have the capabilities to play your high definition videos.
If you have a Mac computer, you will want to use QuickTime media player to be able to see your videos in the mode you recorded them in.
If you have a Windows computer, the media player you use will depend on which version of Windows software you have. For Windows 7 or earlier, you will want to download the media player called 5K Media Player. For Windows 10 or newer, you will want to download VLC Media Player.