diff --git a/src/base/system.c b/src/base/system.c
index 1c4d3a484..f4ce8b37b 100644
--- a/src/base/system.c
+++ b/src/base/system.c
@@ -477,7 +477,7 @@ int lock_try(LOCK lock)
 #if defined(CONF_FAMILY_UNIX)
 	return pthread_mutex_trylock((LOCKINTERNAL *)lock);
 #elif defined(CONF_FAMILY_WINDOWS)
-	return TryEnterCriticalSection((LPCRITICAL_SECTION)lock);
+	return !TryEnterCriticalSection((LPCRITICAL_SECTION)lock);
 #else
 	#error not implemented on this platform
 #endif