The "nlmkv" or ".mkv" extension is a container that holds high-quality video and audio. Standard players like Windows Media Player often lack the necessary codecs to play them.

Compare your file size with the source. If the 720p file is significantly smaller than expected (usually 1GB–1.4GB), the download likely timed out. You will need to redownload the file.

If the video is playing but the audio is out of sync—a common complaint with 720p encodes—you can fix this during playback:

This is the most effective "fix." VLC comes with built-in codecs for MKV files and rarely requires additional configuration.

By following these steps, you should be able to resolve any technical hurdles with your file and enjoy the movie in its intended 720p quality.

In WinRAR, click on the archive, go to Tools , and select Repair archive . 2. Solve "File Format Not Supported"