diff --git a/utils.py b/utils.py
index d68b72cf4470fb3b25660f7b12548328a5bd08cb..44d5b049180a3335c1b252ddc0fd03194e04bf59 100644
--- a/utils.py
+++ b/utils.py
@@ -83,7 +83,7 @@ class MailManager:
         msg["From"] = self.from_addr
         msg["To"] = to_addr
         msg["Subject"] = subject
-        msg["Message-ID"] = "{}@{}".format(uuid4(), getfqdn())
+        msg["Message-ID"] = "<{}@{}>".format(uuid4(), getfqdn())
         msg.attach(MIMEText(content, _charset="utf-8"))
         if appendix is not None:
             for name, file_like in appendix: