diff --git a/src/Microsoft.AspNet.Owin/WebSockets/WebSocketAdapter.cs b/src/Microsoft.AspNet.Owin/WebSockets/WebSocketAdapter.cs
index c9262718d1..1ddc83a499 100644
--- a/src/Microsoft.AspNet.Owin/WebSockets/WebSocketAdapter.cs
+++ b/src/Microsoft.AspNet.Owin/WebSockets/WebSocketAdapter.cs
@@ -134,7 +134,7 @@ namespace Microsoft.AspNet.Owin
                     _webSocket.Abort();
                     break;
                 default:
-                    throw new ArgumentOutOfRangeException(nameof(_webSocket.State), _webSocket.State, string.Empty);
+                    throw new NotSupportedException($"Unsupported {nameof(WebSocketState)} value: {_webSocket.State}.");
             }
         }