diff --git a/configure.ac b/configure.ac
index 1e4543682..301335c35 100644
--- a/configure.ac
+++ b/configure.ac
@@ -116,8 +116,9 @@ dnl set host_os variable
 AC_CANONICAL_HOST
 
 dnl ws2tcpip.h not provided by cygwin and its test causes a configure warning.
+dnl wspiapi.h provides needed freeaddrinfo function on W2k systems.
 AS_IF([test "${host_os}" != "cygwin"], [
-       AC_CHECK_HEADERS([ws2tcpip.h])
+       AC_CHECK_HEADERS([ws2tcpip.h wspiapi.h])
 ])
 
 
diff --git a/lib/getaddrinfo.c b/lib/getaddrinfo.c
index 3cf75ca12..d6586f45f 100644
--- a/lib/getaddrinfo.c
+++ b/lib/getaddrinfo.c
@@ -48,6 +48,9 @@
 #include <sys/socket.h>
 #elif HAVE_WS2TCPIP_H
 #include <ws2tcpip.h>
+#	if defined(HAVE_WSPIAPI_H)
+#		include <wspiapi.h>
+#	endif
 #endif
 
 /*
diff --git a/src/network.c b/src/network.c
index a1ec05eda..214ecd48e 100644
--- a/src/network.c
+++ b/src/network.c
@@ -59,6 +59,9 @@
 #include <sys/socket.h>
 #elif HAVE_WS2TCPIP_H
 #include <ws2tcpip.h>
+#	if defined(HAVE_WSPIAPI_H)
+#		include <wspiapi.h>
+#	endif
 #endif
 
 #include "hamlib/rig.h"
diff --git a/tests/rigctld.c b/tests/rigctld.c
index 8bdee9efb..fd9abb6cc 100644
--- a/tests/rigctld.c
+++ b/tests/rigctld.c
@@ -49,6 +49,9 @@
 #elif HAVE_WS2TCPIP_H
 #include <ws2tcpip.h>
 #include <fcntl.h>
+#	if defined(HAVE_WSPIAPI_H)
+#		include <wspiapi.h>
+#	endif
 #endif
 #ifdef HAVE_NETDB_H
 #include <netdb.h>
diff --git a/tests/rotctld.c b/tests/rotctld.c
index 14da98515..eb4acf5f0 100644
--- a/tests/rotctld.c
+++ b/tests/rotctld.c
@@ -48,6 +48,9 @@
 #elif HAVE_WS2TCPIP_H
 #include <ws2tcpip.h>
 #include <fcntl.h>
+#	if defined(HAVE_WSPIAPI_H)
+#		include <wspiapi.h>
+#	endif
 #endif
 #ifdef HAVE_NETDB_H
 #include <netdb.h>