diff --git "a/dll/win32/msi/dialog.c" "b/dll/win32/msi/dialog.c"
index 7050d353bb7..6d2de804efe 100644
--- "a/dll/win32/msi/dialog.c"
+++ "b/dll/win32/msi/dialog.c"
@@ -2943,8 +2943,16 @@ static UINT msi_dialog_directorylist_up( msi_dialog *dialog )
 
     /* strip off the last directory */
     ptr = PathFindFileNameW( path );
+#if __REACTOS__
+    if (ptr != path)
+    {
+        *(ptr - 1) = '\0';
+        PathAddBackslashW( path );
+    }
+#else
     if (ptr != path) *(ptr - 1) = '\0';
     PathAddBackslashW( path );
+#endif
 
     msi_dialog_set_property( dialog->package, prop, path );