Welcome to our comprehensive guide on Marketo email bounce category 9. As an expert in email deliverability and Marketo usage, I will provide you with valuable insights into this specific bounce category and how to address it effectively. Understanding email bounces is crucial for maintaining a healthy email marketing program and optimizing deliverability. In this article, we will explore the concept of email bounces, delve into Marketo's bounce categories, and focus on category 9 bounces. By the end, you will have a clear understanding of category 9 bounces and the necessary steps to mitigate them.

The Importance of Email Deliverability

Email deliverability plays a vital role in the success of your email marketing campaigns. It refers to the ability of your emails to reach the intended recipients' inboxes rather than being filtered out as spam or bouncing back. Maintaining high deliverability ensures that your messages are seen by your target audience, increasing the chances of engagement, conversions, and overall campaign success.

What Are Email Bounces?

Email bounces occur when an email fails to reach its intended recipient. Bounces can be classified into two main categories: hard bounces and soft bounces. Hard bounces are permanent failures caused by factors like invalid or non-existent email addresses, while soft bounces are temporary issues like a full inbox or a temporary server problem. Marketo classifies bounces into different categories to provide more detailed insights into the reasons behind failed email delivery.

Marketo Email Bounce Categories

Marketo classifies email bounces into ten categories, each representing a specific reason for the failed delivery. These categories help marketers understand the nature of the bounce and take appropriate action to improve deliverability.

The categories are as follows:

1. Category 0: Bounce Category Not Set

2. Category 1: Other

3. Category 2: Suppressed

4. Category 3: Hard Bounce

5. Category 4: Soft Bounce

6. Category 5: Block Bounce

7. Category 6: Spam Block

8. Category 7: Block Bounce External

9. Category 8: Invalid Email Address

10. Category 9: Marketo Suspended

Category 9 Bounces in Marketo

Category 9, also known as 'Marketo Suspended,' refers to bounces caused by Marketo suspending an email address. This can happen due to various reasons, such as multiple hard bounces, spam complaints, or the recipient's email server considering the email as suspicious. When an email address is suspended, Marketo stops sending emails to that address to protect your sender reputation and maintain deliverability to other recipients.

How to Address Category 9 Bounces

If you encounter category 9 bounces in Marketo, there are several steps you can take to address the issue and improve deliverability:

1. Review Bounce Details: Access the bounce details in your Marketo instance to understand why the email address was suspended. Look for patterns or specific reasons mentioned.

2. Verify Email Address: Check if the email address is valid and active. If it's a typo or an invalid address, remove it from your mailing list.

3. Cleanse Your List: Regularly clean your email list to remove inactive or unengaged subscribers. This reduces the likelihood of encountering category 9 bounces.

4. Address Spam Complaints: If spam complaints contributed to the suspension, identify the underlying reasons and take steps to improve your email content, targeting, and permission practices.

5. Monitor Deliverability: Keep a close eye on your email deliverability metrics and monitor any changes in bounce rates or spam complaints. This helps you identify potential issues and take proactive measures.

6. Reach Out to Marketo Support: If you need further assistance with category 9 bounces or have specific questions related to your Marketo instance, don't hesitate to contact Marketo support. They can provide guidance and help you navigate the issue.

Frequently Asked Questions (FAQs)

Q: Can I prevent category 9 bounces in Marketo?

A: While you cannot completely prevent category 9 bounces, you can minimize their occurrence by maintaining a clean and engaged email list, following email best practices, and regularly monitoring your deliverability metrics.

Q: How can I avoid email suspensions in Marketo?

A: To avoid email suspensions, focus on maintaining a good sender reputation by following email marketing best practices, adhering to permission-based marketing principles, and promptly addressing any issues or complaints.

Q: Is it possible to recover a suspended email address in Marketo?

A: Yes, it is possible to recover a suspended email address in Marketo. You can work with Marketo support to understand the reasons for the suspension and take appropriate actions to rectify the situation.

Q: Are there any specific Marketo features or settings that can help with category 9 bounces?

A: Marketo provides various features and settings to help with email deliverability, including bounce management, email validation rules, and spam complaint handling. Familiarize yourself with these features and leverage them to reduce category 9 bounces.


Understanding Marketo email bounce category 9 is crucial for managing your email deliverability and maintaining a healthy sender reputation. By comprehending the reasons behind category 9 bounces and following the recommended steps to address them, you can improve your email campaign performance and ensure that your messages reach your intended audience. Remember to regularly monitor your deliverability metrics, stay up to date with best practices, and leverage the support provided by Marketo. Take control of your email deliverability today and maximize the effectiveness of your Marketo campaigns!