diff --git a/src/ModelEquationBlock.cc b/src/ModelEquationBlock.cc
index 0bd416b8bc38b599e4e16fb1365961f04a786079..224d6db4d405a5f9c3cb3465eb994eccf6557f26 100644
--- a/src/ModelEquationBlock.cc
+++ b/src/ModelEquationBlock.cc
@@ -377,7 +377,7 @@ Epilogue::checkPass(ModFileStructure& mod_file_struct) const
   for (const auto& [symb_id, expr] : dynamic_def_table)
     if (so_far_defined.contains(symb_id))
       {
-        cerr << "WARNING: in the 'epilogue' block, variable '" << symbol_table.getName(symb_id)
+        cerr << "ERROR: in the 'epilogue' block, variable '" << symbol_table.getName(symb_id)
              << "' is declared twice" << endl;
         exit(EXIT_FAILURE);
       }