Many Internet Service Providers (ISPs) and email systems address the problems of SPAM by blocking or filtering email that is not from a "safe sender." To avoid having your campaigns blocked or filtered you will have to work with your list members.
Since your key communications will be sent to your list members exclusively through email, it is very important to ask your list members to add the email.admail.net domain to their list of accepted senders. The first opportunity to do this is on your sign-up form and again when you send your welcome message. We recommend including a reminder like this in your welcome message: "To ensure future delivery of this email copy and paste the following From address to your address book/contact list."
Several IPS have provided whitelisting instructions, which you can use to work with your list members to ensure delivery to their inbox. For directions on how to add email.admail.net to your known sender list click on our FAQ: How do I get my email delivered?
Many of our clients have sent a text email specifically asking their list members to add them to their whitelist (contact list, address book, safe senders list). A practical step which yielded better results on their campaigns.