I import multiple videos into Movie Maker and trim them to ~10 seconds each. After closing out and trying to open the file, all the clips except for the first give an error saying the original file couldn't be found. The file is in the same place with the same name and no alterations. When I locate the same file in the same place, it will automatically give me the portion of the video I wanted. Why do these error messages keep appearing, and how do I prevent it from happening?

I import multiple videos into Movie Maker and trim them to ~10 seconds each. After closing out and trying to open the file, all the clips except for the first give an error saying the original file couldn't be found. The file is in the same place with the same name and no alterations. When I locate the same file in the same place, it will automatically give me the portion of the video I wanted. Why do these error messages keep appearing, and how do I prevent it from happening?