Portable or cracked versions are notorious for crashing, especially during heavy simulations, leading to lost work.
If you are a student or a hobbyist, you can download for free from the Official SideFX Download Page .
If you specifically need Houdini 19 for a project or course, you can still get it officially: Create a free account on the SideFX website.
Using the official build allows you to learn the software exactly as it's used in professional studios. How to Download Old Versions (Like Houdini 19)
Downloading unauthorized versions of Houdini poses several serious risks: