Try www.zamzar.com It's online and free.
You may refer to this guide, it's about how to convert video, including MOV video to AVI video. This way works pretty well for me.
Step 1: Download, install and run Video Converter for Mac
Make sure you download the latest version of Video Converter for Mac, install this software and run it.
Step 2: Load video files
Click Add File button on the top of the main panel to load your desired video such as .mov format files. As batch mode is supported, you can load as many videos as you can at one time.
Step 3: Select output format and path
Hit the drop-down list of Profile to select a proper format that you want to convert to like .AVI, and then click the add file logo ofDestination to browse your computer hard disk to choose a directory to save the converted files.
That is easy with a video converter.
and i have used one for long without any shortcomings.
You can take a try for this one.
Here is the link for the Best video converter i have ever used.
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