Instead, visit the or Imagenomic's official legacy page (if still up) to see if they released v4 as freeware. Spoiler: They haven't. It remains commercial software. Piracy of abandonware is still piracy, and more importantly, it is dangerous.
The Quest for Noiseware Professional 4.1.1.0 for Photoshop 7.0: A Retro Cautionary Tale Instead, visit the or Imagenomic's official legacy page
Instead, download or GIMP for free. You will get better results, you won't get a virus, and you won't be breaking any laws. Have a vintage setup you refuse to let die? Tell us about it in the comments below. Just don't ask us where to find a crack—we value our security (and our karma). and more importantly