diff --git a/ares/ahost.c b/ares/ahost.c
index 1e6cc8bd4..974f94d68 100644
--- a/ares/ahost.c
+++ b/ares/ahost.c
@@ -40,13 +40,6 @@
 #include "inet_net_pton.h"
 #include "ares_getopt.h"
 
-#ifndef HAVE_STRUCT_IN6_ADDR
-struct in6_addr
-{
-  unsigned char s6_addr[16];
-};
-#endif
-
 static void callback(void *arg, int status, int timeouts, struct hostent *host);
 static void usage(void);
 
diff --git a/ares/ares.h b/ares/ares.h
index 5e3431010..37ad9b95c 100644
--- a/ares/ares.h
+++ b/ares/ares.h
@@ -43,8 +43,12 @@
   #include <sys/socket.h>
   #include <tcp.h>
 #elif defined(WIN32)
-  #include <winsock2.h>
-  #include <windows.h>
+#  ifndef WIN32_LEAN_AND_MEAN
+#    define WIN32_LEAN_AND_MEAN
+#  endif
+#  include <windows.h>
+#  include <winsock2.h>
+#  include <ws2tcpip.h>
 #else
   #include <netinet/in.h>
   #include <sys/socket.h>
@@ -241,6 +245,15 @@ int ares_expand_name(const unsigned char *encoded, const unsigned char *abuf,
 int ares_expand_string(const unsigned char *encoded, const unsigned char *abuf,
                      int alen, unsigned char **s, long *enclen);
 
+#ifndef s6_addr
+struct in6_addr {
+  union {
+    unsigned char _S6_u8[16];
+  } _S6_un;
+};
+#define s6_addr _S6_un._S6_u8
+#endif
+
 struct addrttl {
   struct in_addr ipaddr;
   int            ttl;
diff --git a/ares/ares_ipv6.h b/ares/ares_ipv6.h
index afc98320b..6ffa2f375 100644
--- a/ares/ares_ipv6.h
+++ b/ares/ares_ipv6.h
@@ -21,11 +21,13 @@
 #define PF_INET6 AF_INET6
 #endif
 
-#ifndef HAVE_STRUCT_IN6_ADDR
-struct in6_addr
-{
-  unsigned char s6_addr[16];
+#ifndef s6_addr
+struct in6_addr {
+  union {
+    unsigned char _S6_u8[16];
+  } _S6_un;
 };
+#define s6_addr _S6_un._S6_u8
 #endif
 
 #ifndef HAVE_STRUCT_SOCKADDR_IN6
diff --git a/ares/ares_parse_a_reply.c b/ares/ares_parse_a_reply.c
index 4dea80eae..34f2d67e0 100644
--- a/ares/ares_parse_a_reply.c
+++ b/ares/ares_parse_a_reply.c
@@ -32,6 +32,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
 #include "ares.h"
 #include "ares_dns.h"
 #include "ares_private.h"
diff --git a/ares/ares_parse_aaaa_reply.c b/ares/ares_parse_aaaa_reply.c
index 3b578f151..656ffbfb0 100644
--- a/ares/ares_parse_aaaa_reply.c
+++ b/ares/ares_parse_aaaa_reply.c
@@ -34,6 +34,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
 #include "ares.h"
 #include "ares_dns.h"
 #include "inet_net_pton.h"
diff --git a/ares/config-win32.h b/ares/config-win32.h
index 1b65ce764..257a98451 100644
--- a/ares/config-win32.h
+++ b/ares/config-win32.h
@@ -174,19 +174,29 @@
 /* ---------------------------------------------------------------- */
 
 /* Define this if you have address family AF_INET6 */
+#ifdef HAVE_WINSOCK2_H
 #define HAVE_AF_INET6 1
+#endif
 
 /* Define this if you have protocol family PF_INET6 */
+#ifdef HAVE_WINSOCK2_H
 #define HAVE_PF_INET6 1
+#endif
 
 /* Define this if you have struct in6_addr */
+#ifdef HAVE_WS2TCPIP_H
 #define HAVE_STRUCT_IN6_ADDR 1
+#endif
 
 /* Define this if you have struct sockaddr_in6 */
+#ifdef HAVE_WS2TCPIP_H
 #define HAVE_STRUCT_SOCKADDR_IN6 1
+#endif
 
 /* Define this if you have sockaddr_in6 with scopeid */
+#ifdef HAVE_WS2TCPIP_H
 #define HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID 1
+#endif
 
 
 #endif  /* __ARES_CONFIG_WIN32_H */
diff --git a/ares/nameser.h b/ares/nameser.h
index 61741bb5f..154941450 100644
--- a/ares/nameser.h
+++ b/ares/nameser.h
@@ -7,9 +7,6 @@
    port build */
 
 #ifndef NETWARE
-#ifndef __CYGWIN__
-#include <windows.h>
-#endif
 #include <process.h> /* for the _getpid() proto */
 #endif  /* !NETWARE */
 #include <sys/types.h>