diff --git a/repertory.iss.in b/repertory.iss.in
index 06653412..fa4240f5 100644
--- a/repertory.iss.in
+++ b/repertory.iss.in
@@ -30,6 +30,15 @@ UninstallDisplayIcon={app}\{#MyAppExeName}
 WizardStyle=modern
 
 [code]
+const
+  SMTO_ABORTIFHUNG = $0002;
+  HWND_BROADCAST = $FFFF;
+  WM_SETTINGCHANGE = $001A;
+
+function SendMessageTimeout(hWnd: HWND; Msg: UINT; wParam: WPARAM; lParam: LPARAM;
+  fuFlags: UINT; uTimeout: UINT; out lpdwResult: DWORD): LRESULT;
+  external 'SendMessageTimeoutW@user32.dll stdcall';
+
 procedure RefreshEnvironment();
 var
   R: Cardinal;