diff --git a/lib/isc/win32/interfaceiter.c b/lib/isc/win32/interfaceiter.c
index 89c31e3746..8213eba0d4 100644
--- a/lib/isc/win32/interfaceiter.c
+++ b/lib/isc/win32/interfaceiter.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1999-2001, 2004, 2007-2009, 2013-2016  Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 1999-2001, 2004, 2007-2009, 2013-2016, 2018  Internet Systems Consortium, Inc. ("ISC")
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -388,7 +388,7 @@ internal_current6(isc_interfaceiter_t *iter) {
 		iter->current.flags = INTERFACE_F_UP;
 
 		snprintf(iter->current.name, sizeof(iter->current.name),
-			 "TCP/IPv6 Interface %d", iter->pos6 + 1);
+			 "TCP/IPv6 Interface %u", iter->pos6 + 1);
 
 		for (i = 0; i < 16; i++)
 			iter->current.netmask.type.in6.s6_addr[i] = 0xff;
diff --git a/util/copyrights b/util/copyrights
index d889bb4cf3..8253615b7c 100644
--- a/util/copyrights
+++ b/util/copyrights
@@ -4148,7 +4148,7 @@
 ./lib/isc/win32/include/isc/win32os.h		C	2002,2004,2007,2009,2015,2016
 ./lib/isc/win32/include/pkcs11/Makefile.in	MAKE	2014,2016
 ./lib/isc/win32/include/pkcs11/cryptoki.h	X	2014
-./lib/isc/win32/interfaceiter.c			C	1999,2000,2001,2004,2007,2008,2009,2013,2014,2015,2016
+./lib/isc/win32/interfaceiter.c			C	1999,2000,2001,2004,2007,2008,2009,2013,2014,2015,2016,2018
 ./lib/isc/win32/ipv6.c				C	1999,2000,2001,2004,2007,2016
 ./lib/isc/win32/keyboard.c			C	2000,2001,2004,2007,2016
 ./lib/isc/win32/libgen.h			C	2009,2016