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Contributor I
FIRE-FOOD
Contributor I
April 3, 2021
Solved

Bounces t-online.de

  • April 3, 2021
  • 37 replies
  • 4444 views

Hi there - we experience huge problems with bounces to all @t-online.de address (which is Germany’s biggest online provider, hence a big problem for as as Germany is our key market). Essentially all e-mails to @t-online.de bounce for several months already, and we now have several thousand suppressed profiles because of that.

I contacted Klaviyo several times and they always say they will look into it (and trying one more time now), however the problem persists.

Does anyone have any advice on how to best address this? Is this something Klaviyo needs to fix (i.e. is Klaviyo getting blocked), or is our domain the problem? Note we just started to set up our own domain in Klaviyo (have added DNS accordingly), but no results yet.

Also does anyone know how I can un-suppress the profiles in bulk?

Thanks for the help, any advice highly appreciated!

    This topic has been closed for replies.
    Best answer by chloe.strange

    Hi @chris141331 and @superoelk,

    Thank you for surfacing your concerns and @chris141331 for sharing your workaround with the community. 

    We understand that this situation has been challenging and a point of frustration for many, and we appreciate you sharing your feedback and concerns. This issue continues to persist across the industry. @francis.baker shared the steps that we are taking as an organization to improve this experience:

    Hey everyone! 

     

    My name is Francis, I am a Deliverability and Compliance technical specialist here at Klaviyo. I wanted to follow-up on this thread and provide some more information. 

    Klaviyo is actively looking into joining CSA. The CSA application is extensive, and before we can meet all the standards and requirements, they have we need to do some technical changes. We are actively working on these technical changes, as well as working with CSA.

    T-Online is currently not listed as a member of CSA, so yes, the CSA Certification has great benefit. We currently have no evidence, that it will assist with making inbox placement at T-Online easier. Here is a list of all ESP’s and MBP’s that currently take advantage of the CSA Certificate. https://certified-senders.org/participants/

    We understand, how difficult this situation is, and we are all feeling it in the industry. Klaviyo is actively working on ways to make this better and smoother. Deliverability has always been a top priority and will continue to be.

     

    Best,

    Francis 

     

    We'll be closing this thread at this time as we do not have any updates to share. If there is an update to share we will be sure to reopen the topic for visibility. Again, we appreciate your patience and are actively exploring the best strategy for moving this forward.

    Best,

    Chloe

    37 replies

    Show previous replies
    F
    Contributor IV
    flonomao
    Contributor IV
    April 28, 2021

    Hi @Roland, 

    First, we really appreciate your patience as we spent the last few days learning more about T-online.de and how their new restrictions impact our customers. Second, thank you for sharing your concerns around Klaviyo’s urgency around the matter, and the success in the German market. We understand how T-online’s changes on requiring senders to have full domain alignment can create friction for our customers, and we’re hopeful that the guidelines we have created will help our customers navigate these changes more effectively. 

    To clarify for others that might be new to the current T-online.de experience: their new restriction is a global change that was made this past February, which impacts all senders using shared IPs (a common practice across ESPs).

     
    + @flonomao @FIRE-FOOD for visibility into this topic...

    Our team has put together this guide to Meeting the T-online.de Inbox Placement Requirements, which addresses how Klaviyo customers can meet the requirements that T-online has recently outlined: 

    t-online.de Inbox Placement Requirements

    t-online.de has released the following requirements to reach any subscribers who use their inbox service:

    • You must use a dedicated sending IP and have enough consistent volume to keep the IP warm
    • Enable double opt-in for your lists
    • Your Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), Reverse DNS (rDNS; i.e., your domain for dedicated IP), and your sender email domains in Klaviyo (the from-address for each email send) must all align


    While I know this doesn’t provide an immediate fix for our customers who are using a Shared IP today, I’m hoping that the article above will provide some more clarity for how users can get a Dedicated Sending IP, and include better explanation on how we are meeting the new T-online changes.  Additionally, our Academy and Compliance team will continue to monitor and adjust our supporting documentation as updates occur, should T-online revert their requirements. As a second recommendation, I would also suggest reaching out to T-online’s support, or to postmaster@rx.t-online.de, to share the impact this has on your sending volume. 

    Thanks for sharing your experiences on the Community forum with us, and for helping us better understand the impact this has for your business.
    -Cass. 

    Hey @cassy.lee,

    thanks for your detailed answer. Great that your team has put together a small guideline already as well. We’ve now implemented the dedicated sending IP and hope to have solved the problem. Also we hope that it doesn’t have too much impact on our mailing activities.

    Keeping you posted.

      R
      Problem Solver I
      Roland
      Problem Solver I
      April 28, 2021

      Hey @cassy.lee,

      thanks for your guideline to solve the problem.

      Can't it be a bit risky to use a dedicated sending IP? If at the beginning the bounce rate is too high it can happen that the IP gets a spammy environment. Or am I wrong there?

      Also, it would be interesting to know how high the number of mails has to be to keep the IP warm. Do you have an answer for that?

       

      Thanks in Advance!

      @flonomao It´s great to hear that. Please let us know if everything works fine.

      F
      Contributor IV
      flonomao
      Contributor IV
      May 5, 2021

      Hey @cassy.lee and @Roland, 

      we have implemented a dedicated sending IP and did everything that’s mentioned in the guide but t-online mails still bounce. Not sure if we made a mistake or if it’s simply not doing the trick.

      Is it possible to double-check our set-up now from Klaviyo side?

      Best

      Flo

        cassy.lee
        cassy.lee
        Klaviyo Alum
        May 7, 2021

        Hi @flonomao,

        Thanks for your follow up, and letting us know the actions you have taken here. It sounds like perhaps instead of a dedicated sending IP, you were able to get a dedicated sending domain. For clarity, a Dedicated Sending Domain uses the root domain of a business, instead of a root domain supplied by Klaviyo. A Dedicated Sending IP address gives you full control of your email sending, so you're fully responsible for the reputation of your own IP.

        It’s likely that you were able to establish a Dedicated Sending Domain, but there are other specific requirements needed for a Dedicated Sending IP.

        @Roland - you are right that it can be risky to use a Dedicated Sending IP, which is why there are some general guidelines and requirements that restrict access, and there is a defined process for warming that anyone with a Dedicated Sending IP needs to go through. You are correct that if emails from a Dedicated Sending IP have a high bounce rate early on, emails from that Dedicated Sending IP can be marked as spam.

        Regarding your question on appropriate sending volume, according to this Sendgrid article:

        As a general baseline, you should send at least 50,000 emails per month at least twice per month (for 100,000 emails total) in order to warm up your IP.


        We understand that these recent changes implemented by t-online may cause delivery concerns for our customers, and we recognize that not all businesses may meet their requirements for a Dedicated Sending IP. If this is the case for your business, I’d still recommend reaching out to their Support (postmaster@rx.t-online.de) with the specific details of this impact, including:

        - What sending domain you are using
        - # of T-online addresses on file
        - Affirm all addresses are double opt-in (DOI is mandatory for delivery at T-online)
        - Provide example email addresses that have complained to you about not receiving email
        - How many emails do you send each month?
        - Include an email header         https://mxtoolbox.com/Public/Content/EmailHeaders/

        I’d also recommend mentioning that you are a small, growing business and that you need to leverage a shared IP as your business continues to grow, because you currently do not have the volume to keep a dedicated IP warm. Unfortunately, that means you are unable to comply with the domain alignment requirements they have recently rolled out.

        Thanks so much, 
        -Cass. 

          R
          Problem Solver I
          Roland
          Problem Solver I
          May 11, 2021

          Hi @cassy.lee,

          I contacted postmaster@rx.t-online.de as you suggested. They replied in between 30 minutes:

           

          On Tue, 11 May 2021 09:32:42 +0200, you wrote:

          >167.89.100.91

          The error message is addressed to you as the sender of the mail, because the sender should receive a so-called bounce mail (undeliverable message) from the mail server, which contains this error message.

          However, it says that the sender should contact his own postmaster(*) - or alternatively his IT helpdesk - who will, if necessary, contact us in English to clarify the cause of the problem. The e-mail address specified in the error message can also be reached via a mail system that may be blocked by us. 

          (*) You can usually reach your postmaster in the domain from which you received
              received the e-mail with the error message. 

          Sorry for this inconvenience, but we need to have a direct contact with a person responsible for the listed server, as only such a person can solve the problem. Thank you for your understanding!

           

          So, what´s next?

          Best regards

          Roland


           

          cassy.lee
          cassy.lee
          Klaviyo Alum
          May 11, 2021

          Hi @Roland, 

          Thanks for following up with this communication via t-online. I’ve reached out to you via DM to get additional details. 

          Thanks, 
          -Cass. 

          E
          Contributor II
          Erik
          Contributor II
          May 28, 2021

          Hi there,

          we’re facing the same problem. Did you solve the problem by following the mentionted steps in this thread or can you give me any further advice?

          Best

          Erik

          David To
          Klaviyo Employee
          David To
          Klaviyo Employee
          May 28, 2021

          Hello @Erik,

          I’m sorry to hear that you’re experiencing this issue surrounding @t-online emails bouncing and thank you for sharing it with the Community!

          I would first recommend taking a look into the Meeting the T-online.de Inbox Placement Requirements article provided by @cassy.lee within this thread. Our team was able to gather more information from T-Online which has outlined their inbox placement requirement below:

          • You must use a dedicated sending IP and have enough consistent volume to keep the IP warm
          • Enable double opt-in for your lists
          • Your Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), Reverse DNS (rDNS; i.e., your domain for dedicated IP), and your sender email domains in Klaviyo (the from-address for each email send) must all align

          Additionally, I would recommend reaching out directly to T-Online’s Support Team at postmaster@rx.t-online.de with the specific details of how this has  directly impacted your business, including:

          - What sending domain you are using
          - # of T-online addresses on file
          - Affirm all addresses are double opt-in (DOI is mandatory for delivery at T-online)
          - Provide example email addresses that have complained to you about not receiving email
          - How many emails do you send each month?
          - Include an email header https://mxtoolbox.com/Public/Content/EmailHeaders/

          I’ve also reached out to you via a direct message to gather some further information regarding this topic.

          Thanks for being a member of the Klaviyo Community and have a great rest of your day!

          David

           

          C
          Contributor I
          captsirk
          Contributor I
          July 17, 2021

          Hi there, we are facing the same problems with t-online as every german klaviyo user. 

          As i understand we need a dedicated IP. But we don’t sent enough mails to receive one from klaviyo. Is there anything else we can do which is not already mentioned in the above thread?

           

          Does anyone had luck contaction t-online, are they helpful?

           

          Best

            David To
            Klaviyo Employee
            David To
            Klaviyo Employee
            July 19, 2021

            Hey @captsirk,

            The requirement of using a dedicated sending IP was dictated by T-Online. 

            I would suggest reaching out to T-Online to see if they have any available solutions they can provide. Although I do not have any experience reaching out to them myself, from other Community members, it appears that they at have a quick response time to inquiries. If they were able to point you in the right direction, I’m sure the other Community members who are following along would love to hear their suggestion as well!

            Thanks for being a Klaviyo Community Member!

            David

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