diff --git a/TorrentWizard/Strings.h b/TorrentWizard/Strings.h
index 11d4f315e..8556412be 100644
--- a/TorrentWizard/Strings.h
+++ b/TorrentWizard/Strings.h
@@ -22,6 +22,8 @@
 #pragma once
 
 #include <set>
+#include <functional>
+
 
 
 // Produces two arguments divided by comma, where first argument is a string itself