diff --git a/monitor.c b/monitor.c
index 51ab6d6c36c..fb52c335d87 100644
--- a/monitor.c
+++ b/monitor.c
@@ -164,7 +164,11 @@ static char *hostbased_cuser = NULL;
 static char *hostbased_chost = NULL;
 static char *auth_method = "unknown";
 static char *auth_submethod = NULL;
+#ifdef WINDOWS
+static size_t session_id2_len = 0;
+#else
 static u_int session_id2_len = 0;
+#endif /* WINDOWS */
 static u_char *session_id2 = NULL;
 static pid_t monitor_child_pid;