You don't.
You can download VLC from the the VLC website, in the Related links below.
http://www.videolan.org/vlc/
The "SFV" stands for "Simple File Validator" and is used to check the integrity of files. So, you cannot play it using VLC Media Player.
VLC Media Player
VLC is a player not a format a .vlc data file will require the VLC player. The VLC player will play most formats (See links below) and can save files in another format as required.
To reinstall VLC on your computer, first, visit the official VLC website at videolan.org. Download the latest version suitable for your operating system (Windows, macOS, or Linux). After the download is complete, locate the installation file and double-click it to run the installer, then follow the on-screen instructions to complete the installation. Once installed, you can open VLC and begin using it again.
advantages of using ICT
VLC, definitely.
A .mkv file is a High Definition video file. If you're having trouble opening the file try using VLC Media Player. It's free and can be downloaded here: http://www.videolan.org/vlc/
The best avi player is "VLC media player" i preffer using this because, it plays every movie file. It really gives a high quality images. You can get it from http://www.videolan.org/vlc/.
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