This topic explains the technical processes that occur after you send an email in Mapp Engage. Specifically, this topic provides detailed technical information about processing steps and the sequence of these processes.


When you start a sendout in Mapp Engage, you begin an entire cascade of processes. The message content, group members, group settings, sendout settings, selections, blacklists, personalizations, and many more factors are taken into consideration for each sendout! Usually, this process lasts only a few minutes, and your email is underway shortly after sendout starts. Behind the scenes, though, a great deal has already happened.

The following graphic and description give you a high-level overview of the sendout process.

1. Sendout Starts​

In Mapp Engage, sendout is started by a system user, an automation, or an API command. After sendout, your role in the process is complete.

2. Message Storage in the Mapp Engage Database​

In the first step, Mapp Engage stores the message and associated information in the Mapp Engage database. In addition to the text and HTML content of the email, this includes group information, the sendout time, attachments, and other information. This information remains permanently stored in the Mapp Engage database. Mapp Engage uses the information stored in the database to process and send the message.

3. Bulk Mail Creation​

A Mapp Engage APW (Automated Processing Web) automatically retrieves messages stored in the database. The APW creates a bulk mail from the information and produces work packages. Mapp has multiple APWs that can process a large number of messages at the same time. The APW carries out any changes to the bulk message that is valid for all recipients. The personalized email content is added later.

The following table describes the changes that the APW makes to the bulk email, in the correct order.



Leading / Closing Content

Leading content is HTML or text is that is inserted in the body of the email at the beginning of every text message. Closing content is HTML or text is that is inserted in the body of the email at the end of every text message.

Content Merging

Mapp Engage adds content to the message from an external source, such as a website.

Group Attributes

Mapp Engage replaces any placeholders for group attributes in the message with the correct values.

Content Store Elements

Mapp Engage adds images from the content store to the message.

Image Hosting

Mapp Engage loads images that are hosted on the Mapp servers.

Inline Images

Mapp Engage inline images into the message.

Conversion Tracking

Mapp Engage prepares the links in the message for conversion tracking. This involves adding certain parameters to the links in the message.

External Content

Mapp Engage adds content from an external source, such as content added with InsertAd.

Link Tracking

Mapp Engage prepares the links in the message for link tracking. This involves adding certain parameters to the links in the message.

Link Categories

Mapp Engage assigns link categories to the links in the message, if applicable.

Unsubscribe Links

Mapp Engage generates and inserts an unsubscribe link into the email.

Message Activity Tracking

Mapp Engage adds a tracking pixel to the message to track contact activity.

Target Link Parameter

Link parameters are added to links to specify the target address.

4. Creation of Work Packages​

During sendout, Mapp Engage has to create an individual message for each recipient. To make this process faster, Mapp Engage creates numerous work packages of equal size. Dividing the sendout in this way allows Mapp Engage to processes the messages faster.

The work packages are based on groups and the number of members per group. Mapp Engage creates work packages of equal size based on the number of members in the group. Each work segment contains the same number of recipients. A job chunk consists of approximately 500 recipients. Because the actual recipients have not yet been designated at this point, it is still possible for potential recipients to join or leave the group or for them to change their profile data. This is particularly significant in slower sendouts that take place over a longer period of time.

After the work packages are formed, the jobs and bulk messages are stored in the database for further processing. A job is deleted once it has been processed and successfully sent.

5. Message Personalization​

An automated processing tool retrieves the work segments and jobs from the database. This is called the APP (Automated Processing - Personalisation). Mapp Engage has multiple APPs that process the messages simultaneously. First, Mapp Engage personalizes a copy of the message for each contact. Second, Mapp Engage selects the contacts who receive the message.

The processing steps of the APP are as follows:



Expression Language

Mapp Engage replaces any expression language in the message with the correct information or content.


Mapp Engage replaces any placeholders in the message with the correct information or content.

Personalization Rules

Mapp Engage replaces any complex personalization rules (Insert If / Insert Else expressions) in the message with the correct information or content.

Verifying Recipients

Mapp Engage creates the final list of contacts to whom the message is sent. Contacts who are skipped during sendout include the following:

  • Deactivated contacts

  • Selections

  • Message limitations

  • Blacklists and Robinson lists

At this time, Mapp Engage also calculates split sendouts and takes into account whether only a certain percentage of the group is contacted.

Mapp Engage is able to recognize unsubscribes even after sendout has already started.

Personalized Attachments

Mapp Engage adds any personalized attachments to the message.

Individual Links

Personalized links are now personalized for each recipient. A personalized link is a link that contains a placeholder that is replaced during sendout with the value stored in the contact's profile.

6. Message Sendout (Mapp MTA)​

Mapp Engage now transmits each individual message to the Mapp MTA for sendout to each contact. The message is assigned to the appropriate IP pool for sendout.

7. Message ReMapp Engagetion (Recipient MTA)​

The message arrives at the receiving email server. If problems occur (for example, the address does not exist or the mailbox is full), a bounce message is sent to Mapp Engage.

8. Arrival in the Email Inbox​

The contact reads the message in the inbox. The email client may automatically sort the message or classify the message as spam.