While Windows Movie Maker says that it supports popular video formats, but the truth is the application doesn't natively support those video formats until the proper codecs installed. Without having the proper video codecs installed, you may have issues with importing, editing and exporting video [MOV, MP4, AVI, etc…].
As a suggestion for downloading codecs, http://www.free-codecs.com/ has an array of codec packs to choose from. I have used the K-Lite codec pack [standard] for years, and I've had very good success; it even gave me the ability to edit FLV files in Windows Movie Maker. I have never had a problem.
I put this together because there are apparently a lot of people scared to install software if they don't know what it is. So, below is a step-by-step installation with screenshots so people can see what's going to happen before they do any thing.
When you're working with video editing, you may run into situations where the media editor you're trying to work with isn't working properly. There are several reasons for not being able to import video into a video editor, but one of the most common issues is not having the proper codec installed.
If you're new to video editing, the concept of a codec may be completely foreign to you, but this doesn't devalue the requirement for the codec, and the bigger question is, how do you find the proper codec for the video file that you're trying to work with.
Luckily, there is a free application called MediaInfo that will allow you to open and inspect the media file you're trying to work with. The application will give you detailed information about the media file and what codecs are being used to encode the file. In addition to giving you this detailed information, it also gives you options for downloading the proper player and the proper codecs for video editing.
I think everyone has experienced their fair share of difficulties with Windows Movie Maker 2012. It’s fair to say that the application is basic in nature and that Microsoft didn’t intend that Windows Movie Maker would be a high-end video editing package.
My personal experience with Microsoft support was that Windows Movie Maker was intended to encourage me to purchase a separate video editing package if I was going to be doing video editing on a regular basis; and that’s what I did. But I still use Windows Movie Maker from time to time for very simple video editing projects.
I continue to try to assist other Windows Movie Maker 2012 users, through the support forums, and if you spent any time in the support forums, you’ll see a recurring trend of stupid problems with Windows Movie Maker.