diff --git a/dlls/msscript.ocx/msscript.c b/dlls/msscript.ocx/msscript.c
index ee0cf2537e4..1ff330c78a3 100644
--- a/dlls/msscript.ocx/msscript.c
+++ b/dlls/msscript.ocx/msscript.c
@@ -165,6 +165,7 @@ struct ScriptControl {
     IConnectionPointContainer IConnectionPointContainer_iface;
     LONG ref;
     IOleClientSite *site;
+    HWND site_hwnd;
     SIZEL extent;
     LONG timeout;
     VARIANT_BOOL allow_ui;
@@ -2751,8 +2752,12 @@ static HRESULT WINAPI ScriptControl_put_SitehWnd(IScriptControl *iface, LONG hwn
 {
     ScriptControl *This = impl_from_IScriptControl(iface);
 
-    FIXME("(%p)->(%x)\n", This, hwnd);
+    TRACE("(%p)->(%x)\n", This, hwnd);
 
+    if (hwnd && !IsWindow(LongToHandle(hwnd)))
+        return CTL_E_INVALIDPROPERTYVALUE;
+
+    This->site_hwnd = LongToHandle(hwnd);
     return S_OK;
 }
 
diff --git a/dlls/msscript.ocx/tests/msscript.c b/dlls/msscript.ocx/tests/msscript.c
index 5a29c7efc61..8b63e979f02 100644
--- a/dlls/msscript.ocx/tests/msscript.c
+++ b/dlls/msscript.ocx/tests/msscript.c
@@ -1929,7 +1929,7 @@ static void test_SitehWnd(void)
     todo_wine ok(!site_hwnd, "got %p\n", (HWND)(LONG_PTR)site_hwnd);
 
     hr = IScriptControl_put_SitehWnd(sc, 1);
-    todo_wine ok(hr == CTL_E_INVALIDPROPERTYVALUE, "got 0x%08x\n", hr);
+    ok(hr == CTL_E_INVALIDPROPERTYVALUE, "got 0x%08x\n", hr);
 
     site_hwnd = 0xdeadbeef;
     hr = IScriptControl_get_SitehWnd(sc, &site_hwnd);