Campaign Classic - Technical recommendations

Several techniques, configurations, and tools that you can use to improve your deliverability rate when using Adobe Campaign Classic are listed below.

Configuration

Reverse DNS

Adobe Campaign checks whether a reverse DNS is given for an IP address and that this correctly points back to the IP.

An important point in the network configuration is making sure a correct reverse DNS is defined for each of the IP addresses for outgoing messages. This means that for a given IP address, there is a reverse DNS record (PTR record) with a matching DNS (A record) looping back to the initial IP address.

The domain choice for a reverse DNS has an impact when dealing with certain ISPs. AOL, in particular, only accepts feedback loops with an address in the same domain as the reverse DNS (see Feedback loop).

MX rules

MX rules (Mail eXchanger) are the rules that manage communication between a sending server and a receiving server.

More precisely, they are used to control the speed at which the Adobe Campaign MTA (Message Transfer Agent) sends emails to each individual email domain or ISP (for example, hotmail.com, comcast.net). These rules are typically based on limits published by the ISPs (for example, do not include more than 20 messages per each SMTP connection).

TLS

TLS (Transport Layer Security) is an encryption protocol that can be used to secure the connection between two email servers and protect the content of an email from being read by anyone other than the intended recipients.

Sender’s domain

To define the domain used for the HELO command, edit the instance’s configuration file (conf/config-instance.xml) and define a “localDomain” attribute as follows:

<serverConf>
  <shared>
    <dnsConfig localDomain="mydomain.net"/>
  </shared>
</serverConf>

The MAIL FROM domain is the domain used in technical bounce messages. This address is defined in the deployment wizard or via the NmsEmail_DefaultErrorAddr option.

SPF record

An SPF record can currently be defined on a DNS server as a TXT type record (code 16) or an SPF type record (code 99). An SPF record takes the form of a character string. For example:

v=spf1 ip4:12.34.56.78/32 ip4:12.34.56.79/32 ~all

defines the two IP addresses, 12.34.56.78 and 12.34.56.79, as authorized to send emails for the domain. ~all means that any other address should be interpreted as a SoftFail.

Recommendations for defining an SPF record:

• Add ~all (SoftFail) or -all (Fail) at the end to reject all servers other than those defined. Without this, servers will be able to forge this domain (with a Neutral evaluation).
• Do not add ptr (openspf.org recommends against this as costly and unreliable).

Authentication

DKIM

Using DKIM with Adobe Campaign Classic requires the following prerequisite:

Adobe Campaign option declaration: in Adobe Campaign, the DKIM private key is based on a DKIM selector and a domain. It is not currently possible to create multiple private keys for the same domain/sub-domain with different selectors. It is not possible to define which selector domain/sub-domain must be used for the authentication in neither the platform or the email. The platform will alternatively select one of the private keys, which means the authentication has a high chance of failing.

• If you have configured DomainKeys for your Adobe Campaign instance, you just need to select dkim in the Domain management rules. If not, follow the same configuration steps (private/public key) as for DomainKeys (which replaced DKIM).
• It is not necessary to enable both DomainKeys and DKIM for the same domain as DKIM is an improved version of DomainKeys.
• The following domains currently validate DKIM: AOL, Gmail.

Feedback loop

A feedback loop works by declaring at the ISP level a given email address for a range of IP addresses used for sending messages. The ISP will send to this mailbox, in a similar way as what is done for bounce messages, those messages that are reported by recipients as spam. The platform should be configured to block future deliveries to users who have complained. It is important to no longer contact them even if they did not use the proper opt-out link. It is based on these complaints that an ISP will add an IP address to its denylist. Depending on the ISP, a complaint rate of around 1% will result in blocking an IP address.

A standard is currently being drawn up to define the format of feedback loop messages: the Abuse Feedback Reporting Format (ARF).

Implementing a feedback loop for an instance requires:

• A mailbox dedicated to the instance, which may be the bounce mailbox
• IP sending addresses dedicated to the instance

Implementing a simple feedback loop in Adobe Campaign uses the bounce message functionality. The feedback loop mailbox is used as a bounce mailbox and a rule is defined to detect these messages. The email addresses of the recipients who reported the message as spam will be added to the quarantine list.

• Create or modify a bounce mail rule, Feedback_loop, in Administration > Campaign Management > Non deliverables Management > Mail rule sets with the reason Refused and the type Hard.
• If a mailbox has been defined specially for the feedback loop, define the parameters to access it by creating a new external Bounce Mails account in Administration > Platform > External accounts.

The mechanism is immediately operational to process complaint notifications. To make sure this rule is working correctly, you can temporarily deactivate the accounts so that they do not collect these messages, then check the contents of the feedback loop mailbox manually. On the server, execute the following commands:

nlserver stop inMail@instance,
nlserver inMail -instance:instance -verbose.

If you are forced to use one single feedback loop address for multiple instances, you must:

• Replicate the messages received on as many mailboxes as there are instances,

• Have each mailbox picked up by one single instance,

• Configure the instances so that they only process the messages that concern them: the instance information is included in the Message-ID header of messages sent by Adobe Campaign and is therefore located also in the feedback loop messages. Simply specify the checkInstanceName parameter in the instance configuration file (by default, the instance is not verified and this may lead certain address to be quarantined incorrectly):

  <serverConf>
    <inMail checkInstanceName="true"/>
  </serverConf>
  

Adobe Campaign’s Deliverability service manages your subscription to feedback loop services for the following ISPs: AOL, BlueTie, Comcast, Cox, EarthLink, FastMail, Gmail, Hotmail, HostedEmail, Libero, Mail.ru, MailTrust, OpenSRS, QQ, RoadRunner, Synacor, Telenor, Terra, UnitedOnline, USA, XS4ALL, Yahoo, Yandex, Zoho.

List-Unsubscribe

About List-Unsubscribe

Adding an SMTP header called List-Unsubscribe is mandatory to ensure optimal deliverability management.

This header can be used as an alternative to the “Report as SPAM” icon. It will display as an unsubscription link in the email interface.

Using this functionality helps to protect your reputation and feedback will be executed as an unsubscription.

To use List-Unsubscribe, you must enter a command line similar to as follows:

List-Unsubscribe: mailto: client@newsletter.example.com?subject=unsubscribe?body=unsubscribe

The following command line can be used to create a dynamic List-Unsubscribe:

List-Unsubscribe: mailto: %=errorAddress%?subject=unsubscribe%=message.mimeMessageId%

Gmail, Outlook.com, and Microsoft Outlook support this method and an unsubscribe button is available directly in their interface. This technique lowers complaint rates.

You can implement the List-Unsubscribe by either:

• Directly adding the command line in the delivery template
• Creating a typology rule

Adding a command line in a delivery template

The command line must be added in the additional section of the email’s SMTP header.

This addition can be done in each email, or in existing delivery templates. You can also create a new delivery template that includes this functionality.

Creating a typology rule

The rule must contain the script that generates the command line and it must be included in the email header.

1. List-Unsubscribe: <mailto:unsubscribe@domain.com>

   Clicking the unsubscribe link opens the user’s default email client. This typology rule must be added in a typology used for creating email.

2. List-Unsubscribe: <https://domain.com/unsubscribe.jsp>

   Clicking the unsubscribe link redirects the user to your unsubscription form.

   Example:

   

Email optimization

SMTP

SMTP (Simple mail transfer protocol) is an Internet standard for email transmission.

The SMTP errors that aren’t checked by a rule are listed in the Administration > Campaign Management > Non deliverables Management > Delivery log qualification folder. These error messages are by default interpreted as unreachable soft errors.

The most common errors must be identified and a corresponding rule added in Administration > Campaign Management > Non deliverables Management > Mail rule sets if you wish to correctly qualify the feedback from the SMTP servers. Without this, the platform will perform unnecessary retries (case of unknown users) or wrongly place certain recipients in quarantine after a given number of tests.

Dedicated IPs

Adobe provides a dedicated IP strategy for each customer with a ramp-up IP in order to build a reputation and optimize delivery performance.