Hi, I am trying to set up a series of lists meant to behave like sendmail aliases. The idea is to have an address like [log in to unmask] and let the department secretary control who gets mail sent to the address (subscriber control). In general I've got this working. Setting "Default-Options=IETFHDR" helped a lot. The problem is that certain email clients (meaning Outlook) take it upon themselves to read the "Sender:" header line and display it in the "From" field as "<Sender:> on behalf of <From:>. Seems like typical Microsoft making their own rules to me, but Outlook is so common I have to deal with it. Thanks for any help. - Mark