Detail
To import addresses into the Mailing List plug-in, open the WorkgroupMail administrator and double click on the Mailing List Manager entry in the left hand list. This will popup the Mailing List property sheet. Double click on the mailing list that you wish to import addresses into. Select the Members page. Press the Import… button. Select the text file containing the addresses you wish to import and press the Open button. The addresses will be imported. Please note that the imported file must have one email address per line. Each line may take one of the following formats:
mailbox@domain
or
“Name” <mailbox@domain>