Any unknown remote IP address needs to use SMTP AUTHentication (there's a setting in every mail client).
You may also want to search the archives, as this Q has been FA in the extreme. Sandy Please visit http://www.ipswitch.com/support/mailing-lists.html to be removed from this list. An Archive of this list is available at: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/
