Video DownloadHelper operates on a "freemium" model. You can use the basic version for free, but there are specific features and limitations that require a paid license.
Here is the primary difference between the free and paid versions: Video Downloadhelper License Key
If you genuinely cannot afford the license, do not resort to hacking. Use open-source alternatives that are completely free (though less feature-rich): Video DownloadHelper operates on a "freemium" model
If you find yourself needing to download more than a few videos a day, the legitimate path is surprisingly affordable and vastly safer. With one click, you can download it
For the uninitiated, Video DownloadHelper is a browser extension that detects media content streaming in your browser. Instead of digging through page source code or using shady websites to download videos, the extension places a simple icon in your toolbar that animates when a video is detected. With one click, you can download it.
It supports a massive range of sites and file formats, including MP4, WebM, and audio extraction.