diff --git a/UNICADOworkflow/src/clean_up/post_operations_of_workflow.py b/UNICADOworkflow/src/clean_up/post_operations_of_workflow.py
index f60252db4b4e4507310f712973aa25c5c8ff38f5..586b8f065d55eabf878e5a937e63e69e4ff31259 100644
--- a/UNICADOworkflow/src/clean_up/post_operations_of_workflow.py
+++ b/UNICADOworkflow/src/clean_up/post_operations_of_workflow.py
@@ -411,23 +411,23 @@ def post_operations_of_workflow(paths_and_names, control_settings, parameter_for
                                                + aircraft_project + '/engineData')
         for engine in used_engines:
             engine_name = engine.find('./model/value').text
-            for fileName in files_in_engine_directory:
+            for file_name in files_in_engine_directory:
                 # check if fileName a directory
-                if fileName == engine_name:
+                if file_name == engine_name:
                     # if true -> delete engine data from project folder
                     if os.path.isdir(path_of_working_directory_rce + current_workflow_name + '/' + aircraft_project
-                                     + '/engineData/' + fileName) and \
-                                         (fileName not in path_of_working_directory_rce + current_workflow_name 
-                                          + '/temporaryResults/engineData/'):
+                                     + '/engineData/' + file_name) and not\
+                                         (os.path.isdir(path_of_working_directory_rce + current_workflow_name 
+                                          + '/temporaryResults/engineData/' + file_name)):
                         source = path_of_working_directory_rce + current_workflow_name + '/' + aircraft_project \
-                            + '/engineData/' + fileName
+                            + '/engineData/' + file_name
                         destination = path_of_working_directory_rce + current_workflow_name \
-                            + '/temporaryResults/engineData/' + fileName
+                            + '/temporaryResults/engineData/' + file_name
                         shutil.copytree(source, destination)
 
-                        print('Engine ' + fileName + ' has been successfully copied to results folder!')
+                        print('Engine ' + file_name + ' has been successfully copied to results folder!')
                         log_file_list.append(str(datetime.now().strftime('%Y-%m-%d %H:%M:%S')) + ': '
-                                             'Engine ' + fileName + ' has been successfully copied to results folder!')
+                                             'Engine ' + file_name + ' has been successfully copied to results folder!')
 
     ''' copy results of current workflow loop and clean up temporary directory '''
     # call clean-up function of workflow to copy final results to workflow results directory