Why some emails could get in sending queue?

Published by Mailrelay on February 4, 2015

Why some emails could get in sending queue


Sometimes, when you send a mailing, some of the emails of your subscribers can get in sending queue, for a while.

Why does it happen?

That’s what we’ll explain in this article so you know the possible causes and when you will need to contact the support service of our free email newsletter software.

In previous articles we introduced the concept of e-mails in queue, for example due to the volume of emails sent to an ISP.

Today we will see more in detail so that you can understand what you can do if you have this problem.

But first:

Where we can see if some emails are in queue?

When you send a newsletter, if you click on Real time statistics, on your free email newsletter software:

Why some emails could get in sending queue 1


On this screen, you can click the button Detailed sends, on the right:

Why some emails could get in sending queue 2


Now you will see a screen with a menu, (Marked in red), we can filter the emails that are in the send queue:

Why some emails could get in sending queue 3


You can find out how many, and which emails are queued.

Now what do we do?

The first thing is to understand the reasons why these emails are queued, waiting to be sent.

Because that’s exactly what’s happening:

– They are waiting to be sent.

The reasons may vary, but among the most common you will find:

1) Emails rejected due the volume of emails

2) spam-related problems

Usually this happens with major ISPs such as Gmail, Outlook.com, Yahoo, etc. As many smaller filters don’t have the technical infrastructure to block emails.

These “rejections” are not usually definitive, what happens is that the emails are delivered more slowly.

We could say that the filter will allow the emails to gradually pass, to review what is happening, how subscribers react to the newsletter.

This slower number of messages delivered per minute will allow the filter to do just that, to observe and assess the performance of your campaign. So it is normal that the emails are delivered, unless one of the main ISP have blocked the IP, in this case the campaign could be paused.

It is unusual, but it can happen.

In this case, the best thing to do  is to wait about four hours or more, and after this period of time, check the status of the campaign:

– If you notice fewer emails in the queue, you must wait, as  the campaign is being sent

– If the number of emails in queue is the same, you can contact the support staff of our free email newsletter software.

How can we prevent this from happening?

Well, first of all, normally it doesn’t happen.

On the other hand, we cannot avoid it at 100%.

If you have an account on the free email newsletter software offered by Mailrelay, you will be  using shared IPs, as all email marketing  platforms will do, (although if you prefer, You can pay for dedicated IPs). As they are shared, the campaigns of other users who are sharing the IPs will affect your own newsletters.

But if everyone is respecting the best practices of email marketing, we will all benefit.

If you send a newsletter with adequate volume to the reputation of the sender domain, and make everything you can to avoid being marked as SPAM, it will not only help yourself, but it will be better for users who are sending from the same IP.

This is the best thing to do so as to avoid blocking the IPs.

But the sender domain can also be blocked.

We saw in previous articles some information about it, but you should not use newly registered domains as senders.

In the end it comes to following normal good practices.

In short

Some emails may get queued due mainly to an excessive volume of emails sent, for the reputation of the IP or domain, or it could be related with the fact that you have been marked as SPAM several times.

You should verify the campaign status and after a period of time if the number of emails in queue is equal, you can contact the technical support staff of the free email newsletter software.

We hope this article will be helpful!

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  1. Vanessa Carrreras

    Hola, puede ser que un correo quede encolado porque el destinatario reciba muchos mensajes al mismo tiempo. Ejemplo: consultas al gobierno.

    27/10/2021 - 17:20:00 Publicar una respuesta
  2. Jhony Franklin Cárcamo Polanco

    Yo tengo este problema de Encolados la verdad me afecta mucho, ya que acá por correo envío mis tareas y parciales.

    20/08/2021 - 03:35:36 Publicar una respuesta
  3. skan

    Pero no das soluciones.

    14/03/2018 - 19:21:46 Publicar una respuesta
    • Mailrelay

      ¡Hola! En realidad sí, el post indica lo que hay que hacer. Pero si aún tienes duda puedes contactar con nuestro soporte para que revisen tu caso. Normalmente es necesario realizar esta revisión.

      15/03/2018 - 08:32:14 Publicar una respuesta
  4. Fernandors

    Muito obrigado!!
    Muchas gracias
    Esplicações esclarecedoras!!

    07/01/2018 - 12:01:06 Publicar una respuesta
  5. Sergio Cáceres

    En el caso de que una IP haya sido bloqueada por uno de los grandes ISP como procedemos para desbloquearlo???

    12/12/2017 - 09:30:01 Publicar una respuesta
    • Mailrelay

      ¡Hola Sergio! En ese caso es mejor que te pongas en contacto con nuestro soporte para que te puedan ayudar.

      12/12/2017 - 09:31:12 Publicar una respuesta

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