diff --git a/websocket-sharp/Server/HttpServer.cs b/websocket-sharp/Server/HttpServer.cs
index ffbb12bb..195c879c 100644
--- a/websocket-sharp/Server/HttpServer.cs
+++ b/websocket-sharp/Server/HttpServer.cs
@@ -287,10 +287,22 @@ namespace WebSocketSharp.Server
     /// <summary>
     /// Gets or sets the scheme used to authenticate the clients.
     /// </summary>
+    /// <remarks>
+    /// The set operation does nothing if the server has already
+    /// started or it is shutting down.
+    /// </remarks>
     /// <value>
-    /// One of the <see cref="WebSocketSharp.Net.AuthenticationSchemes"/> enum values,
-    /// indicates the scheme used to authenticate the clients. The default value is
-    /// <see cref="WebSocketSharp.Net.AuthenticationSchemes.Anonymous"/>.
+    ///   <para>
+    ///   One of the <see cref="WebSocketSharp.Net.AuthenticationSchemes"/>
+    ///   enum values.
+    ///   </para>
+    ///   <para>
+    ///   It represents the scheme used to authenticate the clients.
+    ///   </para>
+    ///   <para>
+    ///   The default value is
+    ///   <see cref="WebSocketSharp.Net.AuthenticationSchemes.Anonymous"/>.
+    ///   </para>
     /// </value>
     public AuthenticationSchemes AuthenticationSchemes {
       get {