diff --git a/DnsServerCore/Dhcp/Options/OptionOverloadOption.cs b/DnsServerCore/Dhcp/Options/OptionOverloadOption.cs
index 2f075138..8bbaebfb 100644
--- a/DnsServerCore/Dhcp/Options/OptionOverloadOption.cs
+++ b/DnsServerCore/Dhcp/Options/OptionOverloadOption.cs
@@ -1,6 +1,6 @@
 /*
 Technitium DNS Server
-Copyright (C) 2019  Shreyas Zare (shreyas@technitium.com)
+Copyright (C) 2021  Shreyas Zare (shreyas@technitium.com)
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -17,10 +17,12 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
+using System;
 using System.IO;
 
 namespace DnsServerCore.Dhcp.Options
 {
+    [Flags]
     enum OptionOverloadValue : byte
     {
         FileFieldUsed = 1,