diff --git a/library/entropy_poll.c b/library/entropy_poll.c
index eec8ec4..badcfac 100644
--- a/library/entropy_poll.c
+++ b/library/entropy_poll.c
@@ -38,7 +38,7 @@
 #endif
 
 #if !defined(POLARSSL_NO_PLATFORM_ENTROPY)
-#if defined(_WIN32)
+#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
 
 #if !defined(_WIN32_WINNT)
 #define _WIN32_WINNT 0x0400