I installed the Combined Community Codec Pack so that I could view the .m2t files from the Canon HV20 and HV30 cameras. It is free and works great.
You can search for it on the internet.
Download it from here:
https://www.cccp-project.net/
Read about it here:
https://en.wikipedia.org/wiki/Combined_Community_Codec_Pack
Andrew Pitonyak