Most mass e-mail messages include an "opt out" link within the message. To
support this functionality, you'll generally need a web server that can
process each "opt out" request.
Also, some Internet Service Providers (ISP's) limit the amount of bulk mail
that can be sent through their Simple Mail Tranfer Protocol (SMTP) servers.
Users who exceed their limits may be denied service.
Microsoft solves both of these issues with the E-mail Marketing Service.
For additional information on the benefits of this service, see the article
titled "Using the E-Mail Marketing Service in Business Contact Manager" at:
http://office.microsoft.com/en-us/outlook/HP011616031033.aspx