diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index 4e8c0beca8c..9e823582ff6 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -1391,9 +1391,6 @@ The system can be re-made subsequently by just typing <code>make</code>.
   <li>
     <code>CONFIG_NET_LLH_LEN</code>: The link level header length
   </li>
-  <li>
-    <code>CONFIG_NET_EXTERNAL_BUFFER</code>: Incoming packet buffer (uip_buf) is defined externally
-  </li>
   <li>
     <code>CONFIG_NET_FWCACHE_SIZE</code>: number of packets to remember when looking for duplicates
   </li>