Understanding delivery statuses & quarantines
When you send an email, three things can happen:
- the email is accepted → everything is fine
- the email is refused with an error → this is called a bounce
- the user marks the message as spam → this is called a complaint
The refusals (bounces) can be of different types depending on the cause of the error.
Below is a summary table, details follow:
| Status type | Quarantine |
|---|---|
| Hard bounce | Long term |
| Soft bounce – mailbox full | Temporary |
| Soft bounce – domain does not exist | Temporary |
| Soft bounce – message expired | None |
| Spam | None |
Status types
Hard bounce
A hard bounce means that the address is permanently unusable, because:
- it does not exist, or no longer exists
- the account has been deleted
- the domain no longer exists and the server response indicates it is permanent
These addresses are placed in long-term quarantine. The rules are:
- 1st error → long-term quarantine for major public domains
- 2nd error → long-term quarantine for other domains
Quarantines (long term or temporary) are shared across your different databases and across our different clients. The blacklist is specific to your license.
This means that an address in quarantine is, in a way, blocked for all users. However, an address on the blacklist is an address that has specifically blocked your emails.
Soft bounce
A soft bounce means that the email could not be delivered this time, but this is not necessarily permanent, because:
- the mailbox is full
- the domain is temporarily unreachable
- there is an internal system error
- out of office message
- message expired (delivery failed within 48h)
We distinguish three sub-cases according to severity:
- If the mailbox is full, the profile is put into quarantine because this type of issue can negatively impact your reputation
- If the domain is non-existent, the profile is put into quarantine because this shows a data quality issue
- If the message is expired, the profile is not put into quarantine because this is a temporary technical issue
Temporary quarantine durations are progressive:
- 1st time → 1 week
- 2nd time → 2 weeks
- 3rd time → 4 weeks (1 month)
- 4th time → 8 weeks (2 months)
- 5th time → 16 weeks (4 months)
Quarantines (long term or temporary) are shared across your different databases and across our different clients. The blacklist is specific to your license.
This means that an address in quarantine is, in a way, blocked for all users. However, an address on the blacklist is an address that has specifically blocked your emails.
Spam
The webmail server refuses the message because of the reputation or a filter, not because of the address itself.
This can happen when the domain and/or IP reputation is too low, or when the content is considered suspicious.
An ISP considering a message as spam never triggers a quarantine, because the issue comes from the sender’s reputation and not from the quality of the address.
Complaint
A complaint occurs when the user clicks “spam” in their webmail. The profile is then added to the blacklist.
This does not mean that the address is bad, but that the user perceives the message as unwanted.
To receive this information in Actito, a feedback loop must exist for the webmail provider. You mainly receive complaints for Hotmail, Outlook, Yahoo, SFR, La Poste and partially Orange (if the user has enabled the option). Actito also receives complaints for users using the SignalSpam reporting module (which can apply to any domain).
Why is an email quarantined?
There are usually three reasons for an email to be quarantined.
- An email has been sent to a given profile and a hard bounce has taken place. When the domain is well-known, such as @gmail.com or @yahoo.fr, the bounce is trustworthy. In this case, a long-term quarantine starts right after the first message. If it's not a well-known domain (a corporate domain, for example), the quarantine will not be as direct and up to two messages will be allowed before starting the long-term quarantine.
- Several emails are sent over several months to an address and there is always a soft bounce (for example, full inbox). First, a temporary quarantine (one or more weeks) will start. If the issue persists, the address goes into a long-term quarantine.
- A quarantine history from the tool previously used by the client (if that tool is reliable and manages quarantines in a similar way to Actito) is imported and the email addresses are put in quarantine.
Even if we are extremely cautious, an imported history might always contain mistakes. In this case, the source of the error can be identified and a quarantined address could be imposed or lifted to solve the problem. The history import is also verified. When a particularly big license is integrated into Actito, it can be cleaned so as to release the most active quarantined profiles.
If someone clicks on the "Mark as Spam" button (which is a complaint), they will be blacklisted, and all the messages sent by your license to their email address will be automatically filtered. Their profile's blacklist field will show the moment the complaint was issued.
It is possible to release an email address from a blacklist, but the process a bit more complex.
Some "junk" domains are filtered automatically. Some domains, such as "yopmail" for example, offer temporary addresses that will damage your database quality and your deliverability on the long run.
All this information is linked to the email addresses and not to the profiles. This means that a person may leave the quarantine or the blacklist only by changing its email address. Of course, if the new address is not already quarantined or blacklisted.
How to check if an address is quarantined?
It's possible to find out who is quarantined and to use that information in your targeting. However, this is only possible when you have already tried to contact your profiles at least once.
This is how you can find out how many addresses are affected by quarantines and blacklist restrictions:
- For quarantines:
- For quarantines and blacklist:
For a particular profile
If you want to find out the status of a given profile, you can check their profile file. In the "Attributes" section, in the "Technical attributes", there are two fields that will provide you with this information.
The first one is "Blacklisted on": the moment where a profile complained
The second one is "Latest email status": if the address is filtered, it'll be shown here
In the Interactions section you can check, email by email, if they have been filtered and why. If you click on the eye icon, at the right of the email, you'll obtain more information:
Can a quarantine be lifted?
If you want to release a given number of specific quarantined addresses, please contact our support indicating the relevant addresses. You should specify if the quarantine is long-term or blacklist. The procedure is slightly different for blacklist cases, where you will have to take on a part of the process.
When it comes to bigger number of profiles (hundreds or thousands), an in-depth investigation is required to understand why there are so many quarantined addresses.
Is it risky to lift a quarantine?
It is not risky if we are to release just a couple of profiles from long-term quarantines. In the worst case scenario, we would receive hard bounces from them. As long as they do not amount for more than 1% of the campaign, this is not a problem. The profiles would then be quarantined again and, at least this time, we would know that they are rightly so.
However, if we are to release a big number of addresses, the risk of having our bounce rate increased is high and that can impact our deliverability on the long run. In this case the options must be considered on a case by case basis. The strategies will depend on the total volume of your campaigns and the number of addresses affected.
On the other hand, releasing a profile from a blacklist instead of a quarantine is a different process. In this case, the risk is rather legal. For that reason, there's a different procedure in place for which the profile will have to testify that he agrees not being blacklisted anymore.