diff --git a/src/mbox.c b/src/mbox.c
index 2e7902a..411b22a 100644
--- a/src/mbox.c
+++ b/src/mbox.c
@@ -173,7 +173,7 @@ static void
 _mail_mbox_check_mail_parser (Config_Box *cb)
 {
   FILE *f;
-  int header;
+  int header = 0;
   char buf[1024];
 
   if (!cb->new_path)