--- title: "Email Sendout Process" slug: "email-sendout-process" updated: 2025-04-29T09:10:45Z published: 2025-04-29T09:10:45Z --- > ## Documentation Index > Fetch the complete documentation index at: https://docs.mapp.com/llms.txt > Use this file to discover all available pages before exploring further. # Email Sendout Process ## Overview The **Email Sendout Process** in Mapp Engage explains the technical steps that occur behind the scenes when an email is sent. This process ensures that your message is prepared, personalized, and delivered efficiently to each recipient. It also includes advanced options to optimize the sendout speed and timing. Understanding this process helps you: - Monitor and troubleshoot email sendouts. - Optimize message delivery. - Make informed decisions about advanced configuration options such as **Transport Acceleration**. --- ## Navigation Path To view or configure an email sendout: 1. Go to *Messages* > *Draft Messages > Email* 2. Click **Edit**in the **Actions**column. 3. Click **Edit**to move to the Step 2 - Content section. 4. Add your subject line and content, then click **Prepare Sendout**. 5. Configure your sendout settings and click **Check Message**. 6. Review and start or schedule your sendout in the **Summary** step. To view processed messages: *Messages > Outbox* *> Email* --- ## Sendout Workflow and Processing Phases The email sendout process in Mapp Engage includes the following steps: **1 Sendout Start** The sendout is triggered by a system user, automation, or API command. **2 Message Storage** Mapp Engage stores the message content and metadata (group, settings, attachments, etc.) in the database for further processing. **3 Bulk Mail Creation** Mapp Engage creates a bulk version of the message and applies system-level content modifications: | Step | Description | | --- | --- | | **Leading / Closing Content** | HTML or text is inserted at the beginning (leading content) or end (closing content) of every text message. | | **Content Merging** | Content from an external source (e.g., a website) is added to the message. | | **Group Attributes** | Placeholders for group attributes are replaced with actual values. | | **Content Store Elements** | Images from the Content Store are added to the message. | | **Image Hosting** | Images hosted on Mapp servers are loaded into the message. | | **Inline Images** | Images are inserted directly (inlined) into the message body. | | **Conversion Tracking** | Tracking parameters are added to links for conversion tracking. | | **External Content** | Additional external content is inserted (e.g., content via InsertAd). | | **Link Tracking** | Tracking parameters are added to all links in the message. | | **Link Categories** | Links are categorized, if applicable. | | **Unsubscribe Links** | An unsubscribe link is generated and inserted into the message. | | **Message Activity Tracking** | A tracking pixel is inserted to capture recipient activity. | | **Target Link Parameter** | Additional parameters are added to specify the link’s destination target. | **4 Creation of Work Packages** The message is split into work packages (approx. 500 contacts each) to improve processing performance. Recipients are not yet finalized and may still change. **5 Message Personalization** Each work package is personalized for the final recipient list: | Step | Description | | --- | --- | | **Expression Language** | Expression Language (EL) elements in the message are evaluated and replaced with their corresponding content. | | **Placeholders** | Placeholders for contact profile data (e.g., first name) are replaced with actual values. | | **Personalization Rules** | Advanced personalization logic (e.g., *Insert If/Else*) is applied based on contact attributes or behavior. | | **Verifying Recipients** | The final recipient list is generated. Contacts may be excluded due to deactivation, blacklisting, Robinson list membership, selection filters, or message limits. | | **Personalized Attachments** | Individual attachments are added to each contact’s message, if configured. | | **Individual Links** | All message links are personalized for each recipient (e.g., for tracking or redirection). | **6 Message Sendout** Mapp Engage transmits the personalized messages to the Mapp MTA, using the appropriate IP pool. **7 Message Reception** The recipient’s email server (MTA) receives the message. If the address is invalid or the inbox is full, a bounce is generated and returned. **8 Arrival in Inbox** The message is delivered to the inbox or filtered by the recipient’s email client (e.g., into spam or other folders). --- ### Processing Phases Explained The sendout process is divided into two distinct phases: | Phase | Description | Workflow Steps | | --- | --- | --- | | **Message Processing** | Mapp Engage prepares the message: applies selections, personalizations, and creates individual messages for each recipient. | Steps 2–5: Message Storage, Bulk Mail Creation, Creation of Work Packages, Message Personalization | | **Message Transport** | Mapp Engage sends the prepared messages to the recipient's email server (MTA). | Steps 6–8: Message Sendout, Message Reception, Arrival in Inbox | In a standard sendout, these phases occur immediately one after the other. With **Transport Acceleration**, you can schedule message processing in advance, which shortens total sendout time. --- ### Transport Acceleration The **Transport Acceleration** feature allows you to process messages ahead of time to ensure timely delivery. **Benefits:** - Reduces processing time at sendout. - Ensures messages are sent at the exact scheduled time. - Improves transparency and control over sendout timing. - Increases efficiency for large sendouts. For instructions on how to configure this option, see [Configuring an Email Sendout](/v1/docs/configuring-an-email-sendout).