What's New

Blacklisting policy change

the antispam policies of key Internet Service Providers are increasingly restrictive and based on the reputation of the sending list.

One of the most important parameters in defining list reputation is the number of messages sent to inexistent mailboxes (error code 1 "Bad destination mailbox address" in ContactLab). Thus the management of bounced messages (undelivered emails) is fundamental in list "cleanness" policies.

From this point of view, ContactLab was the first player in Italy – later followed by others- to adopt blacklisting policies for repeatedly bounced email addresses.

Since we have been noticing delays in e-mail delivery, in December we met with the e-mail management system executives of the most important international (Hotmail and Yahoo) and Italian (Tin, Alice, Virgilio) ISPs. Based on the feedback received and on the research carried out, we decided to review our blacklisting rules as follows:

From 7 January 2009, all bounce classified as "user unknown",
i.e inexistent email accounts
(Error 1 in ContactLab / Permanent error 5.1.1 RFC 1893 IETF.org)
will no longer be blacklisted the third time anymore, but the first.

Consequently, you will notice a significant increase in blacklisted email accounts starting from the next send-out.