diff --git a/include/boost/config/compiler/visualc.hpp b/include/boost/config/compiler/visualc.hpp
index 3f8b5fe5..5a86b910 100644
--- a/include/boost/config/compiler/visualc.hpp
+++ b/include/boost/config/compiler/visualc.hpp
@@ -79,7 +79,7 @@
 #  if defined(BOOST_ASSERT_CONFIG)
 #     error "Unknown compiler version - please run the configure tests and report the results"
 #  else
-#     warning "Unknown compiler version - please run the configure tests and report the results"
+#     pragma message("Unknown compiler version - please run the configure tests and report the results")
 #  endif
 #endif