{"record":{"id":"ae5ac7591a6a891e","repo":"ramensoftware/windhawk","slug":"failed-to-initialize-minhook","errorCode":null,"errorMessage":"Failed to initialize MinHook","messagePattern":"Failed to initialize MinHook","errorType":"exception","errorClass":"std::runtime_error","httpStatus":null,"severity":"error","filePath":"src/windhawk/engine/customization_session.cpp","lineNumber":218,"sourceCode":"        LOG(L\"AfterInit failed: %S\", e.what());\n    }\n}\n\nCustomizationSession::~CustomizationSession() {\n    try {\n        m_modsManager.BeforeUninit();\n    } catch (const std::exception& e) {\n        LOG(L\"BeforeUninit failed: %S\", e.what());\n    }\n}\n\n#ifdef WH_HOOKING_ENGINE_MINHOOK\nCustomizationSession::MinHookScopeInit::MinHookScopeInit(\n    MH_THREAD_FREEZE_METHOD freezeMethod) {\n    MH_STATUS status = MH_Initialize();\n    if (status != MH_OK) {\n        LOG(L\"MH_Initialize failed with %d\", status);\n        throw std::runtime_error(\"Failed to initialize MinHook\");\n    }\n\n    MH_SetThreadFreezeMethod(freezeMethod);\n\n#ifdef WH_HOOKING_ENGINE_MINHOOK_DETOURS\n    MH_SetBulkOperationMode(\n        /*continueOnError=*/TRUE, [](LPVOID pTarget, NTSTATUS detoursStatus) {\n            LOG(L\"Hooking operation failed for %p with status 0x%08X\", pTarget,\n                detoursStatus);\n        });\n#endif\n}\n\nCustomizationSession::MinHookScopeInit::~MinHookScopeInit() {\n    MH_STATUS status = MH_Uninitialize();\n    if (status != MH_OK) {\n        LOG(L\"MH_Uninitialize failed with status %d\", status);\n    }","sourceCodeStart":200,"sourceCodeEnd":236,"githubUrl":"https://github.com/ramensoftware/windhawk/blob/61d99ed8e182e1af1b60109612b6763ad1b4b74e/src/windhawk/engine/customization_session.cpp#L200-L236","documentation":"Windhawk's customization session initializes the MinHook hooking engine by calling MH_Initialize() during session construction. If MinHook reports any status other than MH_OK (e.g. it was already initialized or an internal buffer allocation failed), the scope constructor logs the status code and throws std::runtime_error to abort the session. A failed hooking-engine init means no hooks can be installed for the customization.","triggerScenarios":"Creating a CustomizationSession with WH_HOOKING_ENGINE_MINHOOK enabled when MinHook is already initialized (MH_ERROR_ALREADY_INITIALIZED), or when MH_Initialize fails to allocate its internal structures.","commonSituations":"Two overlapping customization sessions trying to initialize MinHook in the same process; a previously crashed/partially cleaned-up session leaving MinHook initialized; low-memory conditions.","solutions":["Check whether another customization session or module already called MH_Initialize and is still active; ensure sessions are torn down (MH_Uninitialize) before a new one starts.","Read the logged MH_STATUS code: MH_ERROR_ALREADY_INITIALIZED means MinHook is usable as-is and the throw may be overly strict for your flow.","Retry session creation once the conflicting session has exited.","Report to Windhawk if it reproduces consistently with a single session, including the status code from the log."],"exampleFix":"// before\nMH_STATUS status = MH_Initialize();\nif (status != MH_OK) {\n    LOG(L\"MH_Initialize failed with %d\", status);\n    throw std::runtime_error(\"Failed to initialize MinHook\");\n}\n// after\nMH_STATUS status = MH_Initialize();\nif (status == MH_ERROR_ALREADY_INITIALIZED) {\n    LOG(L\"MinHook already initialized; reusing\");\n} else if (status != MH_OK) {\n    LOG(L\"MH_Initialize failed with %d\", status);\n    throw std::runtime_error(\"Failed to initialize MinHook\");\n}","handlingStrategy":"try-catch","validationCode":"// best-effort pre-check: MinHook is already usable if MH_Initialize would return ALREADY_INITIALIZED\n// no public pre-check exists; catch and inspect the logged MH_STATUS instead","typeGuard":null,"tryCatchPattern":"try {\n    auto session = CreateCustomizationSession(...);\n} catch (const std::runtime_error& e) {\n    if (std::string_view(e.what()) == \"Failed to initialize MinHook\") {\n        LOG(L\"MinHook init failed; retrying after cleanup\");\n        // tear down conflicting sessions, then retry once\n    }\n}","preventionTips":["Ensure each CustomizationSession owns MinHook exclusively; never nest sessions.","Always pair MH_Initialize with MH_Uninitialize on the same thread/lifetime.","Log MH_STATUS codes to distinguish already-initialized vs real failures.","Wrap session creation so a failed init leaves no partially initialized state."],"tags":["windows","hooks","minhook","initialization"],"backgroundTag":"module-init-failed","analyzedSha":"61d99ed8e182e1af1b60109612b6763ad1b4b74e","analyzedAt":"2026-09-12T14:02:41.115Z","contentChangedAt":"2026-09-12T14:02:41.115Z","schemaVersion":2},"datasetVersion":"2026-09-16T09:17:16.951Z"}