Why Get a List Clean?
List cleaning is a crucial part of sending emails to your recipients, as it improves deliverability and reduces the bounce rate of your campaigns. Using lists that have invalid or old email addresses, can reduce the reputation of your IP, which can lead you to become blacklisted. A simple List Clean prevents all of this happening.
The Cleaning Process
Our list cleaning service works in four stages:
- It will first identify any incorrect email addresses, such as those missing an @ sign or those with a space
- The service then validates the domain of the email address (MX lookup)
- Further validation is performed on the email address without sending an email to the intended recipient
- Finally, a deeper scan is performed to ensure the receiving mail server is accepting emails
Once the cleaning is complete, the List Cleaner will categorise each email as one of the following:
The email address does not exist. i.e. Misspelt address, domain doesn’t exist or that alias doesn’t exist at that domain. An Invalid will always be a permanent undeliverable address. So we do not need to differentiate between permanent and temporary errors, as they do not exist.
Undetermined is when we cannot get a concrete response from the destination server. If the MX check doesn’t get a clear response first time, it marks as Undetermined then checks again after 10 secs. If still Undetermined, it checks again after 65 secs. If still Undetermined, the address is marked by the List Cleaner as such. This process is designed to mitigate anti-spam software that rejects multiple requests of the destination server in a single session. Therefore, an email will be checked up to 3 times and then marked as Undetermined – this is due to lack of clear response from the recipient server.
The email is real and able to receive Campaigns.
The List Cleaner will generate the Invalids and Undetermined contacts into an excel file or we can mark as opt-out directly into your send accounts to prevent these contacts being sent to.