diff --git a/dlls/ole32/hglobalstream.c b/dlls/ole32/hglobalstream.c
index 7c78d6809fb..6d20725fa7a 100644
--- a/dlls/ole32/hglobalstream.c
+++ b/dlls/ole32/hglobalstream.c
@@ -563,7 +563,7 @@ static HRESULT WINAPI HGLOBALStreamImpl_LockRegion(
 		  ULARGE_INTEGER cb,          /* [in] */
 		  DWORD          dwLockType)  /* [in] */
 {
-  return S_OK;
+  return STG_E_INVALIDFUNCTION;
 }
 
 /*
diff --git a/dlls/ole32/tests/hglobalstream.c b/dlls/ole32/tests/hglobalstream.c
index df63093bd68..1377741474e 100644
--- a/dlls/ole32/tests/hglobalstream.c
+++ b/dlls/ole32/tests/hglobalstream.c
@@ -71,9 +71,7 @@ static void test_streamonhglobal(IStream *pStream)
     ok_ole_success(hr, "IStream_Revert");
 
     hr = IStream_LockRegion(pStream, ull, ull, LOCK_WRITE);
-    todo_wine {
     ok(hr == STG_E_INVALIDFUNCTION, "IStream_LockRegion should have returned STG_E_INVALIDFUNCTION instead of 0x%08lx\n", hr);
-    }
 
     hr = IStream_Stat(pStream, &statstg, STATFLAG_DEFAULT);
     ok_ole_success(hr, "IStream_Stat");