diff --git a/how_to b/how_to
index 0fb2e94..f04ac7b 100644
--- a/how_to
+++ b/how_to
@@ -1058,3 +1058,6 @@ GPG:
         > expire
         ...
         > save
+
+Windows use realtime clock as UTC:
+    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation\RealTimeIsUniversal = QWORD 0x01