I cannot find specific videos to transfer to my computer

[AC Question]

I have managed to transfer all of my photos, and some of my videos to my PC, the issue I am running into is that only some of my videos are appearing when I have my phone connected as a media device. It is a Samsung Galaxy S5, and the video I am trying to transfer was transferred via Android beam to the phone I had before this one, and then to this phone via an app provided by my carrier. This video is extremely important to me and I need to transfer it to the computer. Any suggestions?