Microsoft's SenderID initiative, which isn't exactly backed by the industry (but as usual, they're going forward with it) will be going live in October 2005. Here's the info:
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What You Need to Do
If you are sending emails to @hotmail.com or @msn.com addresses (you most likely are) you will need to become compliant with Microsoft's Sender ID email verification program before October 2005. After October 2005 all emails that are not Sender ID compliant will not be delivered to Hotmail or MSN email accounts.
Simply paste the following string into the TXT section within your DNS record replacing mail.example.com with your outbound mail server:
" v=spf1 mx a:mail.example.com ip4:216.27.9.96/29 include:icpbounce.com ?all"
To become Sender ID compliant visit http://spf.pobox.com, follow the on-screen wizard to create SPF records, and add the mail server IP addresses of your email marketing company to the list of "Outbound Mail Server Addresses" for your domain. If you use IntelliContact Pro, add the following series that will encompass all IntelliContact Pro's IP addresses:
216.27.9.96/29
If you are not familiar with modifying DNS records you may need to ask for help from your IT department or Web hosting company to complete this process.
Thank you Intellicontact Pro for getting word out to your customers.