diff --git a/src/plugins/platforms/windows/accessible/qwindowsaccessibility.cpp b/src/plugins/platforms/windows/accessible/qwindowsaccessibility.cpp
index 307f2fc3bba2635282d97366910c52e94fee656a..139e1dbecdc46859012137100e8274a17c5390ae 100644
--- a/src/plugins/platforms/windows/accessible/qwindowsaccessibility.cpp
+++ b/src/plugins/platforms/windows/accessible/qwindowsaccessibility.cpp
@@ -159,7 +159,7 @@ void QWindowsAccessibility::notifyAccessibilityUpdate(QAccessibleEvent *event)
     // An event has to be associated with a window,
     // so find the first parent that is a widget and that has a WId
     QAccessibleInterface *iface = event->accessibleInterface();
-    if (!iface) // ### This should not happen, maybe make it an assert.
+    if (!iface || !iface->isValid())
         return;
     QWindow *window = QWindowsAccessibility::windowHelper(iface);