diff --git a/app/controllers/graduation_tasks_controller.rb b/app/controllers/graduation_tasks_controller.rb
index aa7a0eb11..5e48e0139 100644
--- a/app/controllers/graduation_tasks_controller.rb
+++ b/app/controllers/graduation_tasks_controller.rb
@@ -230,7 +230,7 @@ class GraduationTasksController < ApplicationController
 
       o
     end
-    filename = "#{@task.name}_#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}.json"
+    filename = "#{@task.name}_#{Time.now.strftime('%Y%m%d%H%M%S')}.json"
     json = File.open("/tmp/#{filename}", "w+")
     json.puts(person_list.to_json)
     json.close