diff --git a/src/include/winconfig.h b/src/include/winconfig.h
index 1cd1c5df..249e1732 100644
--- a/src/include/winconfig.h
+++ b/src/include/winconfig.h
@@ -1,6 +1,9 @@
 #ifndef _OPENSC_WINCONFIG_H
 #define _OPENSC_WINCONFIG_H
 
+#include <windows.h>
+#include <sys/timeb.h>
+
 #ifndef strcasecmp
 #define strcasecmp stricmp
 #endif
diff --git a/src/libopensc/ctx.c b/src/libopensc/ctx.c
index 72c27807..a1ade2b1 100644
--- a/src/libopensc/ctx.c
+++ b/src/libopensc/ctx.c
@@ -26,9 +26,6 @@
 #include <errno.h>
 #include <sys/stat.h>
 #include <limits.h>
-#ifdef _WIN32
-#include <windows.h>
-#endif
 
 int _sc_add_reader(struct sc_context *ctx, struct sc_reader *reader)
 {
diff --git a/src/libopensc/portability.c b/src/libopensc/portability.c
index 2ddcc3a4..d77b166d 100644
--- a/src/libopensc/portability.c
+++ b/src/libopensc/portability.c
@@ -21,9 +21,9 @@
 #include "internal.h"
 #include <assert.h>
 #include <stdlib.h>
-#ifndef _WIN32
+#ifdef HAVE_SYS_TIME_H
 #include <sys/time.h>
-#else
+#endif
 #include <sys/timeb.h>
 #endif
 
@@ -60,7 +60,6 @@ sc_mutex_free(sc_mutex_t *p)
 	free(p);
 }
 #elif defined(_WIN32)
-#include <windows.h>
 
 sc_mutex_t *
 sc_mutex_new(void)
diff --git a/src/pkcs15init/pkcs15-lib.c b/src/pkcs15init/pkcs15-lib.c
index 121d3efa..9e39c033 100644
--- a/src/pkcs15init/pkcs15-lib.c
+++ b/src/pkcs15init/pkcs15-lib.c
@@ -54,9 +54,6 @@
 #include "profile.h"
 #include "pkcs15-init.h"
 #include <opensc/cardctl.h>
-#ifdef _WIN32
-#include <windows.h>
-#endif
 
 /* Default ID for new key/pin */
 #define DEFAULT_ID		0x45
diff --git a/src/pkcs15init/profile.c b/src/pkcs15init/profile.c
index 4019752e..7946333e 100644
--- a/src/pkcs15init/profile.c
+++ b/src/pkcs15init/profile.c
@@ -37,9 +37,6 @@
 #include <opensc/scconf.h>
 #include "pkcs15-init.h"
 #include "profile.h"
-#ifdef _WIN32
-#include <windows.h>
-#endif
 
 #define DEF_PRKEY_RSA_ACCESS	0x1D
 #define DEF_PRKEY_DSA_ACCESS	0x12
diff --git a/src/scrandom/scrandom.c b/src/scrandom/scrandom.c
index 4bf9dec7..2aec9dd3 100644
--- a/src/scrandom/scrandom.c
+++ b/src/scrandom/scrandom.c
@@ -317,7 +317,6 @@ int scrandom_get_data(unsigned char *buf, unsigned int len)
  */
 
 #include "scrandom.h"
-#include <windows.h>
 #include <wincrypt.h>
 
 int scrandom_get_data(unsigned char *buf, unsigned int len)