diff --git a/cg/cg5100.cpp b/cg/cg5100.cpp
index 823cfc36c..f3201dc1e 100755
--- a/cg/cg5100.cpp
+++ b/cg/cg5100.cpp
@@ -122,10 +122,15 @@ void TParametri_ditta::swap_file(int logicnum, bool tocom)
     dir.set(file, dir.eod(), dir.flags(), dir.des(), dir.expr());
     dir.put(logicnum, _comdir, _sysdirop);
   }
+  else
+    dir.get(logicnum, _unlock, (tocom ? _comdir :_nordir), _sysdirop);
+  
   if (dir.eox() == 0L)
   {
+    set_autoload_new_files(FALSE);
     TSystemisamfile s(logicnum);
     s.build(10L);
+    set_autoload_new_files(TRUE);
   }
 }
 
@@ -206,9 +211,7 @@ bool TParametri_ditta::postprocess_config_changed(const char* par, const char* v
       swap_file(LF_PCON, *newv == 'X');
       swap_file(LF_CAUSALI, *newv == 'X');
       swap_file(LF_RCAUSALI, *newv == 'X');
-      const long firm = get_firm();
-      prefix().set("COM");         
-      set_firm(firm);
+      prefix().reopen();         
       if (*newv == 'X')
       {
         TDir d;