diff --git a/src/include/lwip/opt.h b/src/include/lwip/opt.h
index 4c7b91dd..9b7c6433 100644
--- a/src/include/lwip/opt.h
+++ b/src/include/lwip/opt.h
@@ -927,7 +927,7 @@
  * DHCP_DOES_ACD_CHECK==1: Perform address conflict detection on the dhcp address.
  */
 #if !defined DHCP_DOES_ACD_CHECK || defined __DOXYGEN__
-#define DHCP_DOES_ACD_CHECK             0
+#define DHCP_DOES_ACD_CHECK             1
 #endif
 
 /**