diff --git a/src/UpdaterOptions.cpp b/src/UpdaterOptions.cpp
index 31f5019..ff90e70 100644
--- a/src/UpdaterOptions.cpp
+++ b/src/UpdaterOptions.cpp
@@ -9,7 +9,8 @@
 #include <cstdlib>
 #include <iostream>
 
-#ifdef PLATFORM_WINDOWS
+#if defined(PLATFORM_WINDOWS) && (_MSC_VER < 1800)
+// atoll() was added in MSVC 2013
 long long atoll(const char* string)
 {
 	return _atoi64(string);