diff --git a/src/msw/tooltip.cpp b/src/msw/tooltip.cpp
index 24b7818c97..8277cdfb67 100644
--- a/src/msw/tooltip.cpp
+++ b/src/msw/tooltip.cpp
@@ -465,7 +465,7 @@ void wxToolTip::SetTip(const wxString& tip)
         // for some reason, changing the tooltip text directly results in
         // repaint of the controls under it, see #10520 -- but this doesn't
         // happen if we reset it first
-        ti.lpszText = _T("");
+        ti.lpszText = const_cast<wxChar *>(_T(""));
         (void)SendTooltipMessage(GetToolTipCtrl(), TTM_UPDATETIPTEXT, &ti);
 
         ti.lpszText = const_cast<wxChar *>(m_text.wx_str());