Managing email bounces with mailworx
The intelligent email bounce management of mailworx evaluates all bounces, categorizes them and deactivates them when necessary.
When you are sending thousands of emails it appears that one or another bounces. There are different reasons for bounces: Subscribers change their email address, there might be incorrect addresses because of spelling mistakes or it happens that emails do not exist anymore, because an employee no longer works in a company. Sometimes it is just the case that the inbox is full.
In this guide we want to talk about handling email bounces, types of bounces, bounce limits - which determine after how many failed delivery attempts a subscriber is automatically deactivated - and the things you can do for a better data quality.
Your questions - our answers
If your question hasn´t been answered in this whitepaper, please let us know. We´d gladly catch up on this.
What are bounces and what types of bounces can be distinguished?
Talking about bounces, we mean emails that can't be delivered to an email address. Depending on the type of bounce and the email domain, mailworx will automatically deactivate the subscriber after one or more failed delivery attempts.
We distinguish between three different types of bounces:
- Hard Bounce: Severe and permanent error, e.g. invalid email addresses.
- Soft Bounce: Slight and temporary error, e.g. the subscriber's mailbox is full.
- Spam Bounce: Spam complaints of subscribers lead to this bounce type.
How does mailworx handle bounces?
The bounce limit is the number of failed delivery attempts mailworx allows, before mailworx deactivates the subscriber and excludes the email address from future email campaign sends. There are different bounce limits depending on the type of bounce and the affected email provider. This is because some email providers penalize delivery attempts to invalid email addresses or spam complaints harder than others.
- Hard bounces are deactivated either after the first, or at the latest after the second failed delivery attempt.
- Spam Bounces are deactivated after the first or second failed delivery attempt - depending on the email provider.
- Soft Bounces are temporary errors - usually there is no need to deactivate them. When the email address continues to soft bounce it will be deactivated after 3 to 5 failed delivery attempts.
Why is it necessary to deactivate bounces?
Deactivating bounces automatically and excluding them from future email campaign sends doesn't only reduce the costs of sending. More importantly, it contributes to a high data quality and avoids that you find yourself on an email provider's black list.
Is it possible that bounces get reactivated?
Yes, this is possible in different cases:
Case 1: When the email bounced due to an incorrect email address (e.g. spelling mistake), it will be reactivated automatically after the address has been corrected.
Case 2: When the email was deactivated because of continuing soft bounces, it will be reactivated as soon as the subscriber responds to an email campaign. This will also reset the bounce counter.
A subscriber is on holidays for some weeks and the mailbox runs full. From now on every email delivered to this email address is handled as soft bounce. The subscriber is deactivated after the third failed delivery attempt. When the subscriber cleans up the mailbox back in office, the email address will automatically be reactivated when the subscriber opens the last delivered email.
Where can I see, how many bounces exist in my mailworx account?
When clicking on Subscribers in the navigation, you can see a dashboard with the number of predicted email bounces. When you click on the respective bar, you get to the maintenance area. Another way to get there is over the main navigation Subscribers / Maintenance.
The drop-down-menu allows you to select between the lists of predicted, recognized and already disabled bounces.
If an email address has already bounced before, when sending via the mailworx infrastructure, it will be listed as predicted bounce. As it is not possible to specify the type of bounce, there's no need for you to take action, except that you detect incorrect email addresses or you know about recipients who changed their place of employment.
These email addresses have already led to bounces in your mailworx account. In this list you can also see the bounce statistic. It tells you how many delivery attempts failed so far.
Already disabled bounces
The automatically deactivated email addresses can be found in this list. Check whether you find email addresses that need to be corrected.
Also, take a look at the campaign statistic after sending an email. Here you can see how many emails couldn't be delivered including the affected email addresses and the bounce type.
Should predicted or recognized bounces be deactivated by hand?
As long as there are no email addresses with spelling mistakes that could be corrected, there is no need to take action, because mailworx will deactivate the bounces if necessary. Those subscribers will be labelled as "automatically deactivated" so you will know that the deactivation resulted from a bounce later on.
Of course, it is also possible to deactivate those subscribers by hand, but this makes it more difficult to remember the reason why you did it later on.
What is the difference between invalid email addresses and bounces?
In the maintenance area, you can see the tab "invalid email addresses" next to the tab "bounces". When mailworx notices that an email is incorrect it will exclude it from email campaign send in advance - so there won't be a bounce. Check the list of invalid email addresses temporarily, because most of the time you can detect spelling mistakes that can easily be corrected.
Bounces can also result from invalid email addresses. The difference is that those mistakes can't be identified technically in advance.
What can I do about a large number of bounces due to invalid email addresses?
When you notice that a great number of email addresses has been disabled due to obvious spelling mistakes, that you could easily correct, we recommend the following approach.
- Export the list of "already disabled bounces" and enable the checkbox "Internal ID" for the export. Later you will need the ID as key criterion for the import, as you can't use the email address for the data actualization this case.
- Correct the email addresses in the Excel spreadsheet.
- Import the corrected data as CSV-file and select the internal ID as key criterion.
- Importing the correct email addresses will automatically reactivate the corresponding subscribers and reset the bounce counter.
Is every email that wasn't received from a subscriber assumed to be a bounce?
mailworx displays email addresses as bounces when an email provider reports back an error. There might be cases in which a company uses customized email filters with heavy restrictions. When an email is blocked from the filter, it won't be classified as spam bounce from mailworx because, actually, the email could be delivered successfully. The only reason why the subscriber can't see it, is that it has been blocked from the filter. In most cases, it is possible for the recipient to release those blocked emails.
Tip: When subscribers ask you why they don't receive your emails or you notice that a great number of email addresses from the same company is affected, ask the subscriber to white list your sender domain.
What more can we learn from bounces?
When you notice a great number of spam bounces you should question, whether you've the admission to send emails to the subscribers in your email lists or not. Also, take a look at the content of your campaigns and try to find out what it is that annoys your subscribers. Do you send emails too frequently?
Furthermore, hard bounces could indicate that your contact person in a company doesn't work there anymore. This is good to know for your sales team.