diff --git a/parser.src/ModFile.cc b/parser.src/ModFile.cc
index 6b3d133d83cde8cffcab58acdb84bdb172a7b10e..7f0991f1b46f6eac474a857a7b12812fe2cde1e4 100644
--- a/parser.src/ModFile.cc
+++ b/parser.src/ModFile.cc
@@ -28,13 +28,6 @@ ModFile::checkPass()
       it != statements.end(); it++)
     (*it)->checkPass(mod_file_struct);
 
-//   if (!mod_file_struct.simul_present
-//       && !mod_file_struct.stoch_simul_or_similar_present)
-//     {
-//       cerr << "Error: nothing to compute! you must use one of {simul, stoch_simul, estimation, olr, osr}" << endl;
-//       exit(-1);
-//     }
-
   if (mod_file_struct.simul_present
       && mod_file_struct.stoch_simul_or_similar_present)
     {
diff --git a/parser.src/ParsingDriver.cc b/parser.src/ParsingDriver.cc
index 185ec69da34d3ad559e32e087fe010f37a388326..154109d74dd5253b8a244a368eaa4920bc36c985 100644
--- a/parser.src/ParsingDriver.cc
+++ b/parser.src/ParsingDriver.cc
@@ -154,7 +154,7 @@ ParsingDriver::add_model_variable(string *name, string *olag)
 ExpObj *
 ParsingDriver::add_expression_variable(string *name)
 {
-  //  check_symbol_existence(*name);
+  check_symbol_existence(*name);
   int id = mod_file->symbol_table.getID(*name);
   Type type = mod_file->symbol_table.getType(*name);
   delete name;