diff --git a/repertory.iss.in b/repertory.iss.in
index 4b7265d7..98746b58 100644
--- a/repertory.iss.in
+++ b/repertory.iss.in
@@ -39,16 +39,16 @@ type
   LRESULT = LongWord;
   WPARAM = LongWord;
 
-function SendMessageTimeout(hWnd: HWND; Msg: UINT; wParam: WPARAM; lParam: WideString;
+function SendMessageTimeout(hWnd: HWND; Msg: UINT; wParam: WPARAM; lParam: AnsiString;
   fuFlags: UINT; uTimeout: UINT; out lpdwResult: DWORD): LRESULT;
-  external 'SendMessageTimeoutW@user32.dll stdcall';
+  external 'SendMessageTimeoutA@user32.dll stdcall';
 
 procedure RefreshEnvironment();
 var
-  EnvStr: WideString;
+  EnvStr: AnsiString;
   R: DWORD;
 begin
-  EnvStr := 'Environment' + #0 + #0;
+  EnvStr := 'Environment' + #0;
 
   SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0, 
     EnvStr, SMTO_ABORTIFHUNG, 5000, R);