Your Toughest ISP Questions Answered

Your Toughest ISP Questions Answered

A few weeks ago, SendGrid’s email experts Amy Mustoe and Ryan Harris held a webcast called Google, Yahoo!, and Hotmail, Oh My! Navigating the ISP Landscape. There was so much interest in the topic that Amy and Ryan couldn’t answer all the questions during the webcast. In an effort to continue the conversation, here are responses to all the questions they were unable to get to during the webcast.

For those of you who missed the webcast, access the on-demand version and learn how to stay within the good graces of the ISPs.

How do we do segmentation based on your current stat interface?

Categories are a common way to segment statistics in the SendGrid interface. Categories help organize your email analytics by enabling you to tag emails by type. Just as you can view the statistics on all your activity under the Statistics tab, you can go a step further and view the statistics on a particular category. Within our new stats page, we now offer a COMPARE CATEGORIES section, which allows users to manually select categories to run a side-by-side analysis of data. Main Profile Dashboard, as well as Global Stats, also offer segmentation of data by category.

For true list segmentation you would need to subscribe to our Event API which posts real time stats that can be used to created a segmented list.

Can I somehow see if my email is going into the SPAM folder?

SendGrid, as well as all other ESPs, are limited by the information provided by the ISPs to senders. We are notified that a message was successfully delivered to the ISP. However, once the delivery is made they do not provide further information as to whether the email went to the spam folder or the inbox. Closely watching your open and click rates by ISP can provide great insight into this issue if you see inconsistency across ISPs. There are 3rd Party tools that can give additional insights into inboxing. They are Mail Monitor and Return Path.

Does SG use Feedback Loops (auto-unsubscribe when spam complaints are received from certain ISPs)? If so, is there a list of supported email providers with valid FBLs?

SendGrid automatically registers all users for any major ISPs that offer Feedback Loops. SendGrid then consumes any information returned by these ISP's. They are added to a suppression list. The forward SPAM App allows all SPAM complaints to be forwarded to a specified email address, as well as the tracking that SendGrid offers for all Feedback. Included here is a list of Feedback loops that SendGrid supports on behalf of our customers.
  • AOL
  • Bluetie/Excite
  • Comcast
  • Cox
  • Earthlink
  • Fastmail
  • Hotmail
  • OpenSRS/Tucows
  • Outblaze
  • Rackspace
  • RoadRunner/Time Warner Cable
  • Synacor
  • Terra
  • United Online/Juno/Netzero
  • Yahoo!

Does the spam monitoring only report when a user clicks "spam"?  It seems that we are running into an issue where the users didn't even get to see the email because it already got filtered into the spam folder, and there is no spam reporting from SendGrid?

SPAM reports only include those instances when a user actively marks a message as SPAM.

A lot of my transactional email is going to spam, but my delivered % in SendGrid is 96.45%

Typically this is not norm. There are many factors that could be causing this issue. Please contact SendGrid support and we can dig deeper into the issue.

In Apple's Mail program, the Delete button and Spam button are next to each other. We've found that some people marked us as spam by mistake, meaning to delete the email instead.  Do the ISPs consider this or is a spam marking considered spam no matter what?

Yes, unfortunately, when a user manually clicks the SPAM button for a message, it is considered SPAM. If the user proactively reaches out mentioning the error, feel free to remove them from your SPAM report.

How does one user (e.g., Gmail) marking or deleting my email affect delivery to other users?

ISPs tend to look at overall engagement as well as specific user actions. If they see a lot of non-engagement related to your mail they may start sending a portion to the junk folder for other users. They typically will observe users removing an email from the spam folder “not spam” in the same manner and will starting sending other’s email to the inbox based on overall engagement.

How can you prevent your emails getting sent to the spam folder?

Following email Best Practices is key. Please visit our blog for the latest tips. This one in particular should be viewed.

What are the thresholds for ISPs viewing emails as spam, given that it's common for the majority of emails to not be opened (such as newsletters, promotional offers to existing customers, etc)?

ISPs vary in terms of what they consider a high SPAM threshold. They typically look at the whole picture. This would include bounce rates, engagement, and spam reporting. We suggest not going above .1% for your spam report ratio.

Can you touch on the differences in how to work with transactional emails (order processing, etc) versus marketing/advertising emails? Are there different approaches to achieve high deliverability between the two types?

There are two schools of thought on this topic. The most popular one is segregating your marketing and transactional email into different streams and IPs. This protects your most important mail from a misstep in a marketing campaign.  The second is that by combining the email streams you would get better deliverability overall.

What is the average speed of email delivery?

That is somewhat of a difficult answer. SendGrid passes off email to the ISP within seconds of receiving from our customers. If you are experiencing any delays these are typically based on reputation issues. ISPs decide how much and what frequency to accept your emails based on your domain and IP rating.

Do ISPs see it as a negative to segment subscribers? For example, to segment my subscriber list and send 1 email to 2k Gmail subscribers and then send a separate email to 3k Hotmail subscribers.

ISPs aren't aware what other addresses are on a subscriber list so we don’t feel there would be negative consequences.

A lot of these slides look to target individual companies.  What about Web Companies using your service for relay for 100s of their own clients?

SendGrid fully supports the model of sending on behalf of your customers, we call this an OEM Partner and requires an agreement be signed. By using the Sub-user feature you are also able to segregate and authenticate senders by a specific customer.

If users do not open an email (because it is in their spam box already), what can I do?  Some errors from Gmail that we have seen are: "similar message to other spam message", "contain unrecognized image" (the only image that we have in the mail is the company logo). Suggestions please?

Without knowing exactly the history on this issue I would say first off to call our support department for assistance. In general, once you are in the spam folder it's quite difficult but not impossible to reverse. Your best bet is to send to your most engaged users for a while. This can include new sign ups and those opening and clicking on your emails. Once you are seeing better deliverability you can slowly add back the less engaged users.

Are stats segmented by ISPs available on Sendgrid, or one needs to build custom solutions for this?

Currently, statistics by ISPs are in the private beta stage. Check back to our blog soon. We will be announcing the public beta and how you can participate.

What are your thoughts on sending to Role Accounts (e.g. info@, admin@, etc.)?

SendGrid does not limit your ability to send to Role Accounts. The issue usually comes in when the role account did not opt into the email. As long as addresses used are active and users opt-in you should not have deliverability issues.

What is the intended use of the abuse@ mail addresses?

These are generic addresses used to allow users to reach out directly to a client in order to report incidents of SPAM above a standard SPAM complaint. SendGrid has an abuse@ address for each of our customers with their own IPs at the subdomain level - Some ISPs require these addresses for a valid feedback loop (Yahoo, for example).

Where should you post these email addresses? or postmaster…?

It is not required or even common practice to post this address. The simple fact of having this address to receive complaint email is typically enough.

Is there any way to see or find a "known spam" list ?/

There are companies outside of SendGrid that provide these types of services. SendGrid does not endorse or recommend list cleaning.

This is a general SendGrid question. I love the Email Activity report but I'd like there to be a way to know which email people open.  Right now, if I send multiple emails to someone, I just see that they open an email, but not which one.

The easiest way is to assign categories to your email. They will show in email activity.

How can one automatically measure click and open activity when using SendGrid?

By utilizing the Open and Click Tracking Apps. We will track and report all open and click activities in our standard statistics.

How accurate is your open rate matrix? Is it based on pixel..if so what if images are shut off in a recipient's email box? & How accurate are "open" statistics since they rely on image display, which not everyone does?

Yes, SendGrid uses a pixel in order to track the open rate of HTML emails. Without images enabled we are unable to track the open rate. Due to this limitation you should look at both Open and Click rates.

I've worked on email platforms before that automatically process replies, searching for keywords that would auto-unsubscribe someone. Does SG support this type of functionality (e.g. using a ciphered From/Reply-to Address)?

SendGrid automatically processes replies using our Parse API. We would post back to your URL the parsed email response. It could then be consumed by you and processed as an unsubscribe against your source list or make an API call to add to SendGrid’s unsubscribe list.

We are planning on using our customer service email as the same address as our transactional email. We figured this would help build our rating and help keep our transactional emails more reputable as well because we would be receiving more emails to that address as well. Are there any pitfalls to this or is it a good idea?

This is beneficial when it comes to displaying images or adding the from address as a trusted sender. Using two addresses requires this be done twice by the recipient. The only downside is if there is marketing email that is not well received sharing a from address, it could affect your deliverability on the transactional mail.

What sort of ways would you get people to reply to you when you send a newsletter?  What would be useful?

If you would like them to reply (thereby adding you as a trusted sender) the best way to do this is to have a compelling reason for them to reply. An example would be "reply to this email in order to receive your 20% off coupon."

As for noreply, how will you avoid getting all "away" messages in your inbox?

Our suggestion would be for you to filter those upon receipt.

Should we change our noreply sending address to postmaster and use that email address for sending bulk lists as well as getting the abuse complaints?

It is a best practice to have a valid from address. We do not suggest using abuse in your from address. Those typically get filtered because of the work abuse in them.

How can a business obtain information about specific ISPs in the realm of what they will accept in regards to size of emails, etc.?

SendGrid allows users to send messages up to 20MB in size (including attachments). This is a good upper limit to insure it will comply with all ISPs.

Is it a bad practice to send email using your domain name as opposed to using a subdomain (e.g.

It is not bad practice to send your email using your main domain. There are some drawbacks to this approach. SendGrid’s best practice is to sign all mail using the subdomain for the rDNS, DKIM and from address. Please contact SendGrid support to discuss the options.

We once had an issue where Microsoft blocked 99% of our newsletters. It was very hard to figure out what was wrong. How do you go about troubleshooting to be able to fix the problem if you end up in such a situation?

Microsoft offers an SNDS program, which allows users to monitor the status of their IP reputation. Internal SendGrid alerts also exist to keep customers updated to changes in status with Hotmail/Microsoft reputations.

In order to troubleshoot the issue you would need to look at spam trap hits, your spam and bounce percentages. If those are all low, then looking how your customers are engaging with your messages would be our next suggestion. Are you sending the right message, to the right recipient, and in the right frequency?

What about when you are a shared host, sometimes 1000 domain on single server IP?

SendGrid supports OEM relationships. Please contact our sales department to discuss your options.

Is there a tool to know a domain reputation?

- -

Does Sendgrid offer any type of SLA of the availability of their service?

Please contact SendGrid sales for more information.

0.1% spam threshold is measured over what timeframe? Is it on each mailing or over a timespan like 1month's worth of emails?

The ISPs vary on how they view statistics like spam reports and bounces. It is safe to assume that most IPs do a 30 day look back on metrics. There is one exception. If you are in mid-campaign and the bounce rate or spam rate is high you could see immediate issues even though averaged in the last 30 days the overall rate was low. The same rings true for positive engagement. If you are sending a large campaign and the results are positive the ISPs will respond accordingly.

When I send email via SendGrid, am I using Sendgrid's IP or the IP which is calling SendGrid api?

Sending email through SendGrid utilizes a SG-specific IP, not the IP used to send the email to SendGrid.  If a customer plan is Silver or above, the IP address is unique to that customer.

Is SendGrid submiting Yahoo bulk sender form for all accounts automatically or do we need to request? & If I use SendGrid for transactional emails only, should I manually submit the Yahoo bulk sender form, or does SendGrid do it for me automatically?

For Silver accounts and above with a dedicated IP SendGrid submits on your behalf.

How do I access the feedback loop of Yahoo, Hotmail, AOL etc?

Data provided from feedback loops can be accessed in SendGrid through Email Reports >Spam Reports information available in customer accounts.

When your IP is warming up, do the ISPs first put your email on spam and then gradually move it to the inbox after it's warmed up?

Yes, that is a common practice by most ISPs. They are looking to validate you are sending wanted mail. ISPs handle warm-ups in different ways. It depends on the type of mail you are sending  (marketing vs. transactional) and how gradual the increase is. We suggest you send mail to highly engaged users first, thereby speeding up the likelihood of ISPs accepting larger volumes of emails and sending them to the Inbox v/s SPAM.

What can you do to get on the AOL allow list? Is it automated or can it be requested?

AOL allow list is not automated, you must fill out an allow list form for AOL and it requires 30 days of good sending.

How does someone build their email reputation when they're beginning to send with SendGrid?  We're currently sending hundreds of emails only once a month and quite a large amount of them got filtered into spam (we believe). What should we do?

Large, infrequent sends, tend to mimic SPAM activity, and ISPs don't like to "be surprised." It is suggested that users slowly warm up regular sending patterns, and maintain regular sending to remain in good standing with the ISPs.

What does throttle an email mean exactly?

Throttling usually occurs when an ISP pushes back on our attempt to deliver mail. Look at our docs for more information.

Can you touch on the different throttling policies/metrics of different ISPs? Thx.

ISPs throttle mail based on several factors. The main reason is based on your reputation--you are sending too much mail or too quickly. Until the ISPs know your sending habits and trust your mail they will throttle it to be sure users in general want your mail. As long as you warm up slowly to your final daily volume and have good engagement you should be able to send without much throttling.

Where is this Parse API?

It can be found on the Developers tab of the dashboard. There is more information about the Parse API in our documentation.

Now that I use SendGrid, I find my emails show up in Gmail with their images hidden and a link to "display images." Previously, Gmail displayed my images automatically. I'm not sure what's responsible for the difference?

When users start sending from different ESPs, the user relationships with ISPs change due to the from address as well as the IP and DKIM signature. It is necessary for users to re-establish their preferences within their account to reflect opening practices that they prefer.

Get access to the on-demand version of the webcast here.

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