diff --git a/cxxtest/XmlFormatter.h b/cxxtest/XmlFormatter.h
index b6fd1a2..2322b26 100644
--- a/cxxtest/XmlFormatter.h
+++ b/cxxtest/XmlFormatter.h
@@ -599,7 +599,7 @@ class XmlFormatter : public TestListener
         const time_t now(time(NULL));
         char current_date_string[27];
         
-#ifdef WIN32
+#ifdef _WIN32
         if (ctime_s(current_date_string, sizeof(current_date_string)-1, &now) == 0)
         {
             retVal = current_date_string;