diff --git a/src/core/init.c b/src/core/init.c
index 0eb1e44c..570d54aa 100644
--- a/src/core/init.c
+++ b/src/core/init.c
@@ -141,7 +141,7 @@ PACK_STRUCT_END
 #if (LWIP_TCP && (TCP_WND > 0xffffffff))
   #error "If you want to use TCP, TCP_WND must fit in an u32_t, so, you have to reduce it in your lwipopts.h"
 #endif
-#if (LWIP_TCP && LWIP_WND_SCALE && (TCP_RCV_SCALE > 14))
+#if (LWIP_TCP && (TCP_RCV_SCALE > 14))
   #error "The maximum valid window scale value is 14!"
 #endif
 #if (LWIP_TCP && (TCP_WND > (0xFFFFU << TCP_RCV_SCALE)))
diff --git a/src/include/lwip/opt.h b/src/include/lwip/opt.h
index 0db03b50..61305016 100644
--- a/src/include/lwip/opt.h
+++ b/src/include/lwip/opt.h
@@ -1128,7 +1128,10 @@
 
 /**
  * TCP_WND: The size of a TCP window.  This must be at least
- * (2 * TCP_MSS) for things to work well
+ * (2 * TCP_MSS) for things to work well.
+ * ATTENTION: when using TCP_RCV_SCALE, TCP_WND is the total size
+ * with scaling applied. Maximum window value in the TCP header
+ * will be TCP_WND >> TCP_RCV_SCALE
  */
 #if !defined TCP_WND || defined __DOXYGEN__
 #define TCP_WND                         (4 * TCP_MSS)