diff --git a/CADETProcess/simulator/cadetAdapter.py b/CADETProcess/simulator/cadetAdapter.py
index e53092bd..044f90b0 100644
--- a/CADETProcess/simulator/cadetAdapter.py
+++ b/CADETProcess/simulator/cadetAdapter.py
@@ -235,7 +235,7 @@ def run(self, process, cadet=None, file_path=None):
         except TimeoutExpired:
             raise CADETProcessError('Simulator timed out') from None
         finally:
-            if file_path is None:
+            if not self.use_dll and file_path is None:
                 os.remove(cadet.filename)
 
         if return_information.return_code != 0: