Hello Sidney,
You can check the files if they are supported in Windows Movie Maker by going to the link below:
If your files are supported, please ensure that you have the proper codecs to play your videos and audio files – audio and video require codecs to play the file and it’s important to have the right codecs installed or updated in your PC.
- Try running the Microsoft FixIt tool for codecs: **FixIT**
- Media info will be able to identify any issue with missing or faulty codecs and whether it's already in your computer or not: **Media Info**
As for the Mediainfo, please follow the steps provided below on how to use the program:
- Download Mediainfo
- Install the program
- Run the program
- Open your movie file using Mediainfo
- Switch the view of your mediainfo to text. To do this, click the View button on the upper left part of the window and click text
- When you see the codec that you're lacking, please download it. You can search for the codec in **http://bing.com**
Note: If you can't find the codec you need, try converting the video to a supported format (eg. .wmv for movies, .jpeg/.jpg for photos and .wma for audio) and then add it to your Windows Movie Maker project.
We'll wait for your response.
Thank you.