Unity-Technologies/UnityCsReference · error · ArgumentException

Path {scenePath} is not a scene path. Must end with .unity e

Error message

Path {scenePath} is not a scene path. Must end with .unity extension.

What it means

Thrown by CreateLoadableSceneId when scenePath is non-empty but does not end with the '.unity' extension (case-insensitive). The factory only accepts genuine scene asset paths.

Source

Thrown at Editor/Mono/Loadable/LoadableSceneIdEditorUtility.cs:70

        }

        /// <summary>
        /// Create a LoadableSceneId object based on a scene's path.
        /// </summary>
        /// <param name="scenePath">The scene's path within the project. Must end with .unity extension.</param>
        /// <returns>A LoadableSceneId handle populated to reference the provided scene.</returns>
        /// <exception cref="System.ArgumentNullException">
        /// Thrown if scenePath is null or empty.
        /// </exception>
        /// <exception cref="System.ArgumentException">
        /// Thrown if the path doesn't end with .unity extension or if the scene asset cannot be found at the specified path.
        /// </exception>
        public static LoadableSceneId CreateLoadableSceneId(string scenePath)
        {
            if (string.IsNullOrEmpty(scenePath))
                throw new ArgumentNullException(nameof(scenePath), "Scene path cannot be null or empty.");
            if (!scenePath.EndsWith(".unity", StringComparison.CurrentCultureIgnoreCase))
                throw new ArgumentException($"Path {scenePath} is not a scene path. Must end with .unity extension.");
            var guid = new GUID(AssetDatabase.AssetPathToGUID(scenePath));
            if (guid.Empty())
                throw new ArgumentException($"Couldn't locate scene asset at path {scenePath}");
            return CreateLoadableSceneId(guid);
        }
    }
}

View on GitHub (pinned to 225b0fbdb5)

Solutions

1. Ensure the path passed is the AssetDatabase path of an actual SceneAsset.
2. Constrain the picker/construction to SceneAsset so the extension is always correct.
3. Normalize/append '.unity' only if the input is genuinely a scene path that lost its extension.

Example fix

// before
var id = LoadableSceneIdEditorUtility.CreateLoadableSceneId(assetPath);

// after
if (!assetPath.EndsWith(".unity", StringComparison.OrdinalIgnoreCase))
    throw new ArgumentException($"{assetPath} is not a scene.");
var id = LoadableSceneIdEditorUtility.CreateLoadableSceneId(assetPath);

if (!scenePath.EndsWith(".unity", System.StringComparison.OrdinalIgnoreCase)) throw new ArgumentException("Not a scene path.");

static bool IsScenePath(string p) => p != null && p.EndsWith(".unity", System.StringComparison.OrdinalIgnoreCase);

try { CreateLoadableSceneId(scenePath); }
catch (ArgumentException ex) when (ex.Message.Contains(".unity")) { Debug.LogError(ex.Message); }

When it happens

Trigger: Passing a path to a non-scene asset (.prefab, .unity scene excluded on purpose, .asset), a directory path, or a path with the wrong extension. Also a typo in the extension.

Common situations: A UI that lets users pick any Object instead of a SceneAsset. Code that derives a scene path by string manipulation and drops or misspells the extension. Mixing prefab and scene concepts.

Related errors

• Scene path cannot be null or empty.
• Preview scene could not be created
• Couldn't locate scene asset at path {scenePath}
• No material targets provided
• src

AI-assisted analysis of Unity-Technologies/UnityCsReference@225b0fbdb5 (2026-08-13). Data as JSON: /api/errors/8b7881f0ed9c4c80. Report an issue: GitHub.