diff --git a/Source/MQTTnet/Server/MqttServerTlsTcpEndpointOptions.cs b/Source/MQTTnet/Server/MqttServerTlsTcpEndpointOptions.cs
index f0b54160..0c529b57 100644
--- a/Source/MQTTnet/Server/MqttServerTlsTcpEndpointOptions.cs
+++ b/Source/MQTTnet/Server/MqttServerTlsTcpEndpointOptions.cs
@@ -1,6 +1,8 @@
 using System.Net.Security;
 using System.Security.Authentication;
+#if !WINDOWS_UWP
 using System.Security.Cryptography.X509Certificates;
+#endif
 
 namespace MQTTnet.Server
 {