Warming Up IP Addresses: 5 Steps for Faster Inbox Placement

If you had talked to any email marketer 10 years ago and asked them how they dealt with blocks on their IP addresses, the answer would probably be the same: “We just switched IPs.” Not only was this an unfortunate, albeit effective, way to deal with blocks, it also became a common method used by spammers. They would simply send from one IP address for a very short time and then move on to another, either with IPs they owned or through hijacked computers controlled by botnets. Because of spammers’ behaviors, ISPs and email providers respond by temporarily blocking and limiting the amount of email a new IP address could send. ISPs now treat any new sending IP address like a dog on a short leash, and only extend the leash when the senders’ reputation is proven.

As a result of this filtering and blocking behavior, senders are better off improving their sending reputation instead of hopping on to a new IP address. Properly warming up an IP address takes time, and most senders will find it can take a month or longer before they are sending to the volumes they were accustomed to. Fixing a reputation is usually much easier and senders can see better results in matter of weeks, if not days. There are a couple of reasons you still might have to send from a new IP address, such as moving to a new ESP, moving to a new data provider, or moving off of Goodmail. Goodmail had a unique way of tokenizing their customers’ mail by relaying mail through their own IP addresses, and consequently their reputation. Therefore, once you stopped using Goodmail, your traffic now goes through your IPs, which hasn’t had any traffic in awhile, which means you’ll need to work on building up your sending reputation again.

To minimize the impact of having to move to a new IP address, consider the following:

1. Sign up for all feedback loops. When a subscriber clicks on the spam button, that’s recorded as a complaint and is negatively counted against you. You can receive a copy of those that complain by signing up for feedback loops, and then suppress them from future mailings. Treat these complaints seriously by treating them like an unsubscribe request. This can go a long way to reducing your complaint rates and increasing your sending reputation.

2. Authenticate. Make sure that your new sending IP address is in all of your SPF and Sender ID records. Make sure that you’re also signing with DKIM. ISPs like Gmail are tying your reputation scores to your authentication records, which mean that your new IP may be able to get a longer leash if it’s part of your authentication records that have a good reputation.

3. Segment and mail your active subscribers. You can build a good sending reputation much faster if you start by mailing to your most active subscribers first. You’re probably also thinking that this is your most profitable segment so you’re not comfortable mailing to those first since they’ll probably experience delivery issues. While this is true, the pain will be only short lived. By mailing your most active subscribers first, you may decrease your time to warm up your IP addresses by weeks.

4. Monitor. The volume of mail that you can expect to send on an hourly or daily basis is strongly tied to your email reputation, especially during the warm-up period. Monitor your reputation and deliverability by using a seed-list based monitoring system like Mailbox Monitor. This will give you essential information on your inbox placement rates and help guide you on which ISPs you need to focus. I also recommend monitoring your bounce logs on a daily basis and looking for issues that show you’ve exceeded volume limitations. Additionally, monitor your IP addresses at email reputation sources like Sender Score. Once your reputation scores improve, you can start increasing sending volumes, and apply for publicly available whitelists.

5. Get Certified. Being accredited as a good mailer through Return Path’s Certification can minimize some of the scrutiny your new IP addresses will have to go through. Since we’ve already looked at your mailing practices inside and out, you don’t have to get vetted out again by email providers. You can skip the warm-up period and enjoy the benefits of inbox placement and the other benefits that Certification has to offer.

If this looks like a lot of work, then you’re right. To be successful, you need to plan appropriately, be patient, send smarter, and constantly monitor. Whether you’re switching IP addresses or moving to a new ESP, we can help. Contact us at http://www.returnpath.net/contact/ to see how.

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