diff --git a/wxdata/source/scwx/util/time.cpp b/wxdata/source/scwx/util/time.cpp
index 52ff076f..ea664e2e 100644
--- a/wxdata/source/scwx/util/time.cpp
+++ b/wxdata/source/scwx/util/time.cpp
@@ -59,7 +59,7 @@ std::string TimeString(std::chrono::system_clock::time_point time,
 {
    using namespace std::chrono;
 
-#if !(defined(_MSC_VER) || defined(__clang__))
+#if (defined(_MSC_VER) || defined(__clang__))
 #   define FORMAT_STRING_24_HOUR "{:%Y-%m-%d %H:%M:%S %Z}"
 #   define FORMAT_STRING_12_HOUR "{:%Y-%m-%d %I:%M:%S %p %Z}"
    namespace date = std::chrono;