If you're running a discussion list (listserve), make sure your Settings are set to a Discussion Forum / Listserve.
To actually send a message, you or any other list subscriber should create an email message with your List ID as the To: address. For instance, if your List ID were knitting-list, the message would be sent To: firstname.lastname@example.org.
You may also wish to check your Reply-To: settings. If responses to list messages should go to all subscribers (best for lists where there's ongoing discussion), make sure your Reply-To is set to "Everyone on the list".
If responses should go only to the person who sent the message, set the Reply-To to "Just the original sender". Please note that someone who did not hit Reply, but Reply All, or who CC's their message to the list address, can still have their reply go to everyone on the list.
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