Missing Metrics: Your Questions Answered

For our recent webinar The Hidden Metrics of Deliverability, I discussed the engagement metrics that mailbox providers can use to determine filtering, and how marketers can use these metrics in their own programs. We had so many great questions in this webinar we decided to do a follow-up blog post for questions we didn’t have time to answer.

Yahoo states they base reputation on DKIM, not IP address reputation. What does that mean for how they view my email?
Yahoo designed DomainKeys which later combined parts of Cisco’s Identified Internet Mail to become DomainKeys Identified Mail, or DKIM. Yahoo has been authenticating email using DomainKeys or DKIM for nearly a decade now. They have been tying a sender’s reputation to DKIM for nearly as long. Gmail also authenticates using DKIM, as well as SPF and DMARC and use this information to better understand the behavior and reputation of senders.

What is the best way to build a strong sender reputation when setting up a new domain or IP address?
It depends on whether you are starting from scratch or moving an existing email program to a new domain or IP address. If it’s a new mail program, sign up for all feedback loops, authenticate using SPF, DKIM, and DMARC, and use permission-based sign ups. If you’re migrating to a new IP address and/or domain, read these articles for some advice on warming an IP address. Many of the tactics are still valid for new email programs. You just won’t need to worry about slowly ramping volume, segmentation, etc. For more information on how to warm an IP address, check out these blog posts:

How Warm is Warm? Thinking About Your IP Address Warm-Up Process
Why a Sending History is Important to Reaching the Inbox
Warming Up IP Addresses: 5 Steps for Faster Inbox Placement

Most requirements seem to apply to marketing/promotional emails. Is there a separate list Return Path uses for customers who want to get Return Path Certified for transactional emails only?
We have many customers that use Certification on transactional emails. As long you meet the requirements of the program, it doesn’t matter if your emails are promotional or transactional.

How can I get more information about what good email infrastructure looks like?
I’d recommend reading this blog post as a good primer for what to look for in a good email infrastructure.

Which ISPs enable image by default?
Gmail, Yahoo, and Microsoft all enable images by default for good senders with positive mailing reputations.

If I am a third party, sending emails on behalf of my clients through an ESP, how do I see the hidden metrics and the associated sender score?
These hidden metrics, as well as reputation data related to Sender Score, is available through Return Path’s Inbox Insight and Reputation Monitor products. Please contact us to see how you can use these tools to monitor your clients’ metrics.

What is the difference between your read rate and your open rate?
The open rate and read rate are similar, but at Return Path, we refer to our metric as the read rate since it doesn’t rely on images being enabled to record an open like the open rate does.

Where can you find your read rate and your deleted without reading rate? Is this a function of the in-house email software?
At Return Path, we are able to observe the read rate and deleted without reading rate through our panel of 2.5 million real-life subscribers.

What is a good open rate?
We recommend looking at the read rate benchmark for your industry in our Hidden Metrics of Email Deliverability Report.

Can Return Path identify which subscribers mark my email as “this is not spam?”
We are not able to identify email addresses marking a sender as “not spam” due to privacy reasons. Senders can only identify subscribers who mark an email as spam via feedback loops at mailbox providers that offer them.

What is a sender’s unique open rate and does Return Path measure it?
Our read rate is based on unique reads and doesn’t include multiple opens from the same subscriber.

What can we do to remove the red unlock button in Gmail?
You will need to encrypt your emails using Transport Layer Security (TLS) encryption and authenticate your emails with SPF and DKIM.

We have a lot of emails that go into the ‘promotions’ folder in Gmail. How do they decide to put emails in that tab instead of the ‘primary’ or ‘spam’ tab?
If you send promotional emails, it’s not recommended to have your emails delivered to the ‘primary’ tab. Mail that isn’t identified as promotional is given more scrutiny and has a higher chance of being delivered to the spam folder. To avoid being delivered to the spam folder, sign up for Gmail’s Postmaster Tools to help diagnose deliverability issues.

Was there a recent change at Gmail that spiked the spam rate globally?
You can read this recent blog post about the deliverability issues some senders were recently experiencing at Gmail.

I have been trying to convince a client that buying a list is unwise—any good advice to tell him?
Purchased lists are not typically maintained by the list owner and are often riddled with spam traps and unknown users. For the email addresses that are valid mailable, permission wasn’t received and typically results in high complaints. As a result, most senders destroy their sending reputations, and future emails will be blocked or sent to spam. The money spent on purchasing the list and the time and effort spent repairing their reputation usually makes purchasing lists a money-losing tactic. If you need to build a list, but don’t have the time to grow it organically, there are some list rental services that could work. Or you can send them our new eBook, 50+ Ways to Grow Your Email List.

What is the best option for a mailbox full of errors? Should these subscribers be unsubscribed?
It’s not necessary to unsubscribe these addresses. If they are abandoned, eventually they will return an “unknown user” code, and your bounce processing system should disable or unsubscribe them at that point.

If this error is a cost issue or causing email server performance issues, many senders will disable soft bounces after a certain period of re-tries over a certain period of time with no success—like 10 consecutive soft bounces in a 14-day period. The frequency and cadence of your mailings should inform your own specific case.

AOL will return an “unknown user” hard bounce message for 12-18 months? Not a soft bounce, correct?

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