Occasionally, a subscriber address is misconfigured and automatically sends a message back to the list. Sometimes, the subscriber's setup has removed headers that ezmlm uses for loop detection or the generated messages has nothing in common with the send-out. To block such mail at the list, include the ezmlm-make(1) -k (kill) switch and add the offending address to DIR/deny/ with
% ezmlm-sub DIR deny badadr@badhost
ezmlm-unsub(1) and ezmlm-list(1) can be used similarly to remove or list the addresses. If your list is configured for remote administration (see How remote administration works), and you are a remote administrator, you can add the address by sending mail to ‘list-deny-badadr=badhost@listhost’. Other subscriber database commands work as well for ‘list-deny’.
In other instances, a configuration error somewhere close to the subscriber creates a local mail loop throwing off messages to you. They are often bounces that are sent to the list address or to ‘list-help’ due to configuration errors. Rather than accepting these, or the often resulting double bounces to ‘postmaster’, just add a ‘|/path/ezmlm-weed’ line first to DIR/editor or DIR/manager. This discards the bounce messages generated by the looping systems. ezmlm-weed(1) is also useful in other settings where excessive numbers of error messages are sent to the wrong address.