diff --git a/crypto/rand/windows.c b/crypto/rand/windows.c
index 7bfcb1d2..1a0cb8b0 100644
--- a/crypto/rand/windows.c
+++ b/crypto/rand/windows.c
@@ -27,7 +27,7 @@
  * "Community Additions" comment on MSDN here:
  * http://msdn.microsoft.com/en-us/library/windows/desktop/aa387694.aspx */
 #define SystemFunction036 NTAPI SystemFunction036
-#include <NTSecAPI.h>
+#include <ntsecapi.h>
 #undef SystemFunction036
 
 #pragma warning(pop)
diff --git a/crypto/thread_test.c b/crypto/thread_test.c
index cecda883..e028b1be 100644
--- a/crypto/thread_test.c
+++ b/crypto/thread_test.c
@@ -22,7 +22,7 @@
 #if defined(OPENSSL_WINDOWS)
 
 #pragma warning(push, 3)
-#include <Windows.h>
+#include <windows.h>
 #pragma warning(pop)
 
 typedef HANDLE thread_t;