diff --git a/websocket-sharp/Server/WebSocketServer.cs b/websocket-sharp/Server/WebSocketServer.cs
index 1867d78f..bb7c5c1d 100644
--- a/websocket-sharp/Server/WebSocketServer.cs
+++ b/websocket-sharp/Server/WebSocketServer.cs
@@ -1261,8 +1261,15 @@ namespace WebSocketSharp.Server
     /// it is shutting down.
     /// </remarks>
     /// <exception cref="InvalidOperationException">
-    /// There is no configuration used to provide secure connections or
-    /// the configuration has no server certificate.
+    ///   <para>
+    ///   There is no configuration for secure connections.
+    ///   </para>
+    ///   <para>
+    ///   -or-
+    ///   </para>
+    ///   <para>
+    ///   There is no server certificate.
+    ///   </para>
     /// </exception>
     /// <exception cref="SocketException">
     /// The underlying <see cref="TcpListener"/> has failed to start.