# Operational email, sender options and A/B tests

*Marketing Cloud Account Engagement Specialist Study Guide · Email Marketing · Last updated November 3, 2026 · https://www.certifyforce.com/study-guide/marketing-cloud-account-engagement-specialist/email-marketing/operational-email-sender-options-and-a-b-tests*

What qualifies as operational email and who can receive it, how mailability, Do Not Email and suppression lists decide recipients, how sender hierarchies and reply-to addresses work, how classic A/B tests pick and send a winner, and how to reschedule or pause a list email.

- Certification: Salesforce Marketing Cloud Account Engagement Specialist
- Exam section: Email Marketing
- Study guide: https://www.certifyforce.com/study-guide/marketing-cloud-account-engagement-specialist

**Official exam objective:**

> Given a scenario, identify the capabilities and use cases for email.

## What the exam expects

- Decide whether a message is operational or marketing, and which tools can send an operational email.
- Predict who receives a send from mailability status, Do Not Email, opt-out, bounces and suppression lists.
- Build a valid sender hierarchy with a fallback, and separate the sender from the reply-to address.
- Set up a classic A/B test (one variable, criterion, test percentage, duration) and predict who gets which version.
- Reschedule or pause a list email, knowing what the enhanced experience can't do.

Key terms:
- **Operational email**: a critical, non-marketing message that bypasses marketing opt-in status.
- **Mailability status**: Mailable, Operational Emails Only, Prospect is in Recycle Bin or Undeliverable.
- **Do Not Email**: a prospect field that suppresses one prospect from marketing email without changing opt-in.
- **Suppression list**: a list that omits its prospects from a list email or engagement program.
- **Sender hierarchy**: an ordered set of senders checked from the top at send time.

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Operational sending | List emails and Engagement Studio, not automation rules | [Non-Marketing Emails](https://help.salesforce.com/s/articleView?id=mktg.pardot_operational_emails.htm&type=5&language=en_US) |
| Enable operational email | Account Engagement Administrator role | [Enable Operational Email](https://help.salesforce.com/s/articleView?id=mktg.pardot_operational_email_enable.htm&type=5&language=en_US) |
| Undeliverable | One hard bounce or five or more soft bounces | [Mailability Status](https://help.salesforce.com/s/articleView?id=mktg.pardot_prospect_mailability.htm&type=5&language=en_US) |
| Autoresponders | Treated as operational; opted-out prospects still get them | [Mailability Status](https://help.salesforce.com/s/articleView?id=mktg.pardot_prospect_mailability.htm&type=5&language=en_US) |
| Suppression list types | Any non-test list, static or dynamic | [Suppression Lists](https://help.salesforce.com/s/articleView?id=mktg.pardot_segmentation_suppression_lists.htm&type=5&language=en_US) |
| Last sender in hierarchy | Specific User or General User with a verified domain | [Sender and Reply-To](https://help.salesforce.com/s/articleView?id=mktg.pardot_email_sending_options.htm&type=5&language=en_US) |
| No reply-to set | Replies go to the sender address | [Sender and Reply-To](https://help.salesforce.com/s/articleView?id=mktg.pardot_email_sending_options.htm&type=5&language=en_US) |
| A/B minimum audience | At least four prospects | [Trailhead](https://trailhead.salesforce.com/content/learn/modules/pardot-email-marketing-lightning/test-and-send-an-email-lightning) |
| A/B tie | Version A is sent | [Trailhead](https://trailhead.salesforce.com/content/learn/modules/pardot-email-marketing-lightning/test-and-send-an-email-lightning) |
| A/B completion actions | Apply to A, B and the winner | [Enable A/B Testing](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_ab_test.htm&type=5&language=en_US) |
| Reschedule | Classic list emails only | [Reschedule](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_cancel_scheduled_send.htm&type=5&language=en_US) |
| Pause a send | Total Queued row of the List Email report | [Pause a Send](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_pause_list_email_send.htm&type=5&language=en_US) |

## Check yourself

- Why might prospects in a running program skip a Send Operational Email step?
- When does an email with a valid saved hierarchy still fail to send?
- Why are role-based addresses a poor General User choice?
- What happens to the countdown when a paused A/B test is unpaused?

## Sources

- [Sending Non-Marketing Emails](https://help.salesforce.com/s/articleView?id=mktg.pardot_operational_emails.htm&type=5&language=en_US)
- [Enable Operational Email Sending](https://help.salesforce.com/s/articleView?id=mktg.pardot_operational_email_enable.htm&type=5&language=en_US)
- [Operational Emails in Engagement Studio Limitations](https://help.salesforce.com/s/articleView?id=mktg.mcae_operational_emails_engagement_studio.htm&type=5&language=en_US)
- [Prospect Mailability Status](https://help.salesforce.com/s/articleView?id=mktg.pardot_prospect_mailability.htm&type=5&language=en_US)
- [Suppress Prospects from Receiving Emails](https://help.salesforce.com/s/articleView?id=mktg.pardot_prospect_suppression.htm&type=5&language=en_US)
- [Suppress Multiple Prospects with a Suppression List](https://help.salesforce.com/s/articleView?id=mktg.pardot_segmentation_suppression_lists.htm&type=5&language=en_US)
- [Sender and Reply-To Options](https://help.salesforce.com/s/articleView?id=mktg.pardot_email_sending_options.htm&type=5&language=en_US)
- [Enable A/B Testing for an Email](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_ab_test.htm&type=5&language=en_US)
- [Considerations for Using A/B Testing](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_ab_considerations.htm&type=5&language=en_US)
- [Email Testing & A/B Testing Strategies (Trailhead)](https://trailhead.salesforce.com/content/learn/modules/pardot-email-marketing-lightning/test-and-send-an-email-lightning)
- [Considerations for Designing and Sending Emails](https://help.salesforce.com/s/articleView?id=mktg.pardot_eilex_content_builder_considerations.htm&type=5&language=en_US)
- [Send a List Email](https://help.salesforce.com/s/articleView?id=mktg.pardot_send_list_email.htm&type=5&language=en_US)
- [Reschedule a List Email](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_cancel_scheduled_send.htm&type=5&language=en_US)
- [Pause a List Email Send](https://help.salesforce.com/s/articleView?id=mktg.pardot_emails_pause_list_email_send.htm&type=5&language=en_US)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 13 linked practice questions, and unlimited timed mock exams are included with the Marketing Cloud Account Engagement Specialist pack (USD $19): https://www.certifyforce.com/practice-exams