Harry Potter And The Chamber Of Secrets, despite being targeted ad children, is actually a pretty good game.
Released in late 2002 by EA Games, it was one of the last games to use the Unreal Engine 1. The game was also released on PlayStation 1 and 2, Xbox, and even Gameboy, and surprisingly, all these versions are very different, developed by completely different teams using different engines, and they're all pretty good. Ah, those were the days.
Being this recent, this game doesn't have too many problems: the CD check doesn't work but there's a crack for that, and we have graphical issues that we have to fix.

First of all, install the game. You will need a CD key, found in the game's box.
The installer still works fine on Windows 10, but at the end it says that the system is incompatible. Ignore it and don't run the game yet.
Download these patched files and extract them to the game's folder replacing the existing files: English (International) | English (USA) | Italian | French | German | Spanish | Brazilian Portuguese | Swedish | Norwegian | Japanese.
How does the fix work?

If you ran the game before, you will also have to open My Documents, enter the Harry Potter II folder and delete Game.ini, as shown in the screenshot below

Finally, try to run the game from the shortcut on your desktop. The game will take a few seconds to start after the logos.

When you get to the menu, enter the video settings and make sure Direct3D is selected, along with the highest resolution supported by your screen.
The game only supports resolutions up to 1024x768. Higher resolutions can be forced by modifying Game.ini but the UI doesn't scale well and it's basically unplayable in widescreen, so I suggest you stick with 1024x768.

And now you can enjoy the game!

If the current version of the fix doesn't work for you, here are some older versions: 2019 version | 2016 version

Leave a comment or contact me and I'll help you out.

Harry Potter and the Sorcerer's Stone on Windows 10