diff --git a/websocket-sharp/Server/WebSocketServer.cs b/websocket-sharp/Server/WebSocketServer.cs
index f39c50ae..4438db01 100644
--- a/websocket-sharp/Server/WebSocketServer.cs
+++ b/websocket-sharp/Server/WebSocketServer.cs
@@ -221,7 +221,7 @@ namespace WebSocketSharp.Server
     public WebSocketServer (int port, bool secure)
     {
       if (!port.IsPortNumber ()) {
-        var msg = "It is less than 1 or greater than 65535.";
+        var msg = "Less than 1 or greater than 65535.";
         throw new ArgumentOutOfRangeException ("port", msg);
       }