June 3, 2023
4:36 p.m.
On Sun, 4 Jun 2023, Stephen J. Turnbull wrote:
Date: Sun, 4 Jun 2023 02:01:35 +0900 From: Stephen J. Turnbull <turnbull.stephen.fw@u.tsukuba.ac.jp>
If that doesn't reveal the reason, also check your MTA logs and configuration. MTAs are usually configured to reject or discard huge messages (I think Postfix defaults to 50MB), and that would happen before getting to Mailman.
Postfix has TWO such limits: message_size_limit and mailbox_size_limit.
They're both set in main.cf, which is usually found in /etc/postfix.
HTH, RT