If you are trying to get the 2004 PC game running on modern systems like Windows 10 or 11, common fixes include:
If you are looking for the definitive way to watch Prisoner of Azkaban in 1080p without the technical flaws of the past, follow these steps: harry potter and the prisoner of azkaban 2004 1080p fix
If you are looking at threads concerning the 1080p movie files floating around the web (often titled as "fixes", "open matte", or "extended editions"): The Reality of "Open Matte" for Film 3: Enthusiasts at communities like Fanrestore If you are trying to get the 2004