@yuanjunquan Sorry for the troubles. Normally you should only receive a warning which says that the Animation class name already exists, but no compile error stating that the type could not be found. How did you install the spine-unity runtime? Did you install it via the unitypackage and then move the directories to Assets/Framework/ThirdLibs/Spine? Or did you install it in a different way, e.g. via the Unity Package Manager (if so, how exactly did you install it)?

Which Unity Editor version are you using?

@yuanjiashun Thanks for posting the additional information. This is indeed strange. If the error is just displayed after moving the folder and no error is displayed before moving it, it sounds like a bug with Unity's asset management or code project generation system.

If you want to avoid the issue in the future, you could place the spine directories outside the Assets folder so that Unity does not find it (e.g. outside projectname/Assets in projectname/Modules/Spine/) and then add it via the Unity Package Manager as local package, via Add Package from Disk.. as described here for UPM packages.

@yuanjiashun Please note that you can still modify the source code when placing them locally in e.g. projectname/Modules/Spine and add the UPM package via Add package from Disk.. instead of Add package from git URL...

I'm not sure I understand the machine translation of the section regarding GetOrCreateSettings correctly. Are you saying that if you don't modify the source code, you receive an error when GetOrCreateSettings is executed and the file does not exist yet? This should not happen, as the settings asset should be created automatically when it does not exist (in this code section). If you receive an exception, are you using the latest version of the 4.1 or 4.2-beta runtimes?