diff --git a/websocket-sharp/Server/WebSocketServer.cs b/websocket-sharp/Server/WebSocketServer.cs
index 41acafbf..cb45cb21 100644
--- a/websocket-sharp/Server/WebSocketServer.cs
+++ b/websocket-sharp/Server/WebSocketServer.cs
@@ -583,7 +583,8 @@ namespace WebSocketSharp.Server
     public ServerSslConfiguration SslConfiguration {
       get {
         if (!_secure) {
-          var msg = "This instance does not provide secure connections.";
+          var msg = "The server does not provide secure connections.";
+
           throw new InvalidOperationException (msg);
         }