Advance-authorized list of email addresses, held by an ISP, subscriber or other email service provider, which allows email messages to be delivered regardless of spam filters. See also enhanced white list.
3 Quick And Easy Ways To Build A Profitable Opt-In List
You finally realize that you need a good opt-in list. After reading countless articles and sought expert advices and have read many success stories of people creating a small fortune with opt-in lists you finally decide to have one of your own.
