{"record":{"id":"ebf9e61b1b72be26","repo":"Unity-Technologies/UnityCsReference","slug":"prefab-not-found-at-path-prefabassetpath","errorCode":null,"errorMessage":"Prefab not found at path {prefabAssetPath}","messagePattern":"Prefab not found at path (.+?)","errorType":"validation","errorClass":"ArgumentException","httpStatus":null,"severity":"error","filePath":"Editor/Mono/SceneManagement/StageManager/PrefabStage/PrefabStageUtility.cs","lineNumber":99,"sourceCode":"\n        public static PrefabStage OpenPrefab(string prefabAssetPath, GameObject openedFromInstance, PrefabStage.Mode prefabStageMode)\n        {\n            return OpenPrefab(prefabAssetPath, openedFromInstance, prefabStageMode, StageNavigationManager.Analytics.ChangeType.EnterViaUnknown);\n        }\n\n        internal static PrefabStage OpenPrefab(string prefabAssetPath, GameObject openedFromInstance, PrefabStage.Mode prefabStageMode, StageNavigationManager.Analytics.ChangeType changeTypeAnalytics)\n        {\n            if (string.IsNullOrEmpty(prefabAssetPath))\n                throw new ArgumentNullException(nameof(prefabAssetPath));\n\n            if (openedFromInstance != null && !PrefabUtility.IsPartOfPrefabInstance(openedFromInstance))\n                throw new ArgumentException(\"GameObject must be part of a Prefab instance, or null.\", nameof(openedFromInstance));\n\n            if (!prefabAssetPath.EndsWith(\".prefab\", StringComparison.OrdinalIgnoreCase))\n                throw new ArgumentException(\"Incorrect file extension: \" + prefabAssetPath + \". Must be '.prefab'\", nameof(prefabAssetPath));\n\n            if (AssetDatabase.LoadMainAssetAtPath(prefabAssetPath) == null)\n                throw new ArgumentException(\"Prefab not found at path \" + prefabAssetPath, nameof(prefabAssetPath));\n\n            return OpenPrefabMode(prefabAssetPath, openedFromInstance, prefabStageMode, changeTypeAnalytics);\n        }\n\n        static PrefabStage GetExistingPrefabStage(string prefabAssetPath, GameObject openedFromInstance, PrefabStage.Mode prefabStageMode)\n        {\n            var stageHistory = StageNavigationManager.instance.stageHistory;\n            for (int i = 1; i < stageHistory.Count; i++)\n            {\n                var prefabStage = stageHistory[i] as PrefabStage;\n                if (prefabStage != null && prefabStage.assetPath == prefabAssetPath)\n                {\n                    // If PrefabStage.Mode did not match on existing PrefabStage we do not reuse the stage\n                    // so we create a new PrefabStage with the correct mode\n                    if (prefabStage.mode == prefabStageMode)\n                        return prefabStage;\n                }\n            }","sourceCodeStart":81,"sourceCodeEnd":117,"githubUrl":"https://github.com/Unity-Technologies/UnityCsReference/blob/225b0fbdb57cc17d094e8056b71f8314aba56f73/Editor/Mono/SceneManagement/StageManager/PrefabStage/PrefabStageUtility.cs#L81-L117","documentation":"Thrown by PrefabStageUtility.OpenPrefab when AssetDatabase.LoadMainAssetAtPath(prefabAssetPath) returns null, meaning no asset exists at the given path. This validates that the prefab file actually exists in the project before attempting to open a stage for it.","triggerScenarios":"Passing a path to a prefab that has been moved, renamed, or deleted. Typo in the path. Asset not yet imported or the path is relative in an unexpected way. Prefab exists in a package but the path is malformed.","commonSituations":"Hardcoded asset paths that go stale after refactoring. Paths constructed at runtime that don't match the actual asset location. Assets in Addressables or packages where the path convention differs.","solutions":["Verify the asset exists with AssetDatabase.LoadMainAssetAtPath before calling OpenPrefab.","Use AssetDatabase.FindAssets or GUID-based lookups to resolve the path dynamically.","Refresh the AssetDatabase if the asset was recently added."],"exampleFix":"// before\nPrefabStageUtility.OpenPrefab(path, null, mode);\n\n// after\nif (AssetDatabase.LoadMainAssetAtPath(path) != null)\n    PrefabStageUtility.OpenPrefab(path, null, mode);\nelse\n    Debug.LogError($\"Prefab not found at {path}\");","handlingStrategy":"validation","validationCode":"bool PrefabExists(string path)\n{\n    return !string.IsNullOrEmpty(path) && AssetDatabase.LoadMainAssetAtPath(path) != null;\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Resolve asset paths via AssetDatabase.GUIDToAssetPath rather than hardcoding.","Call AssetDatabase.Refresh() before looking up recently added assets."],"tags":["unity","prefab","editor","asset-database","validation"],"backgroundTag":null,"analyzedSha":"225b0fbdb57cc17d094e8056b71f8314aba56f73","analyzedAt":"2026-08-13T19:07:19.849Z","schemaVersion":2},"datasetVersion":"2026-08-13T19:17:28.613Z"}