Why do posts appear to be from “listname-bounces@mailman.u.washington.edu on behalf of” the sender rather than from the senders actual email address?
When a message is sent to a Mailman list, Mailman adds a Sender header that looks like this: Sender: listname-bounces@mailman.u.washington.edu [listname-bounces@mailman.u.washington.edu] On Behalf Of name of sender Some email programs such as MS Outlook read this Sender header rather than the original From header but label it as the From header. Only people using MS Outlook (or other programs that behave in the same way) will see the From line in this way. Most programs will display the correct From line with the original sender’s name and address.
