Summary
Migrating to HubSpot can lead to high Barracuda bounce rates due to factors affecting sender reputation, authentication, and filtering. Key issues include Barracuda blocking AWS IP ranges used by HubSpot/Amazon SES, exceeding Barracuda's scoring thresholds, and the new environment triggering Barracuda's filters. Addressing this requires a multi-faceted approach:
* **Technical**: Implement and validate SPF, DKIM, and DMARC for email authentication; check and resolve any issues with your sending infrastructure setup, and warm up the new IP address/sending domain gradually.
* **Reputation**: Monitor and address issues with your sender reputation, including RBL listings and spam complaints; maintain good list hygiene (remove hard bounces and unengaged subscribers) and avoid content that triggers spam filters.
* **Filtering**: Investigate if shared domains are blocked by Barracuda; warm up Barracuda domains slowly; understand that Barracuda may perform automated security checks impacting reported metrics and consider engaging Barracuda support.
* **Monitoring**: Monitor email bounce rates closely and take swift action to identify and resolve technical/list issues; compare metrics against industry benchmarks to detect significant deviations.
Key findings
- Barracuda's Spam Filtering: Barracuda's anti-spam filters are flagging emails after migrating to HubSpot, leading to high bounce rates.
- Sender Reputation Problems: Sender reputation issues, such as being listed on RBLs or having a poor sending history, can cause Barracuda to block emails.
- Authentication Configuration Errors: Incorrect or missing SPF, DKIM, and DMARC records result in authentication failures, causing Barracuda to reject emails.
- List Hygiene Issues: Sending emails to invalid or unengaged email addresses increases bounce rates, further damaging sender reputation.
- AWS IP Range Blocks: Barracuda might be blocking entire AWS IP ranges, which HubSpot uses via Amazon SES, causing legitimate emails to bounce.
- Shared Domain Reputation: HubSpot's shared IP reputation may be negatively impacting deliverability.
- Lack of Warmup: Failing to warm up a new IP address or sending domain properly can cause deliverability issues.
- Barracuda Score Threshold Exceeded: Messages are blocked based on Barracuda scoring policies.
Key considerations
- Email Authentication Implementation: Implement and validate SPF, DKIM, and DMARC records to ensure proper email authentication.
- Sender Reputation Management: Monitor sender reputation using tools like Google Postmaster Tools and take steps to address any issues.
- List Hygiene Practices: Implement strict list hygiene practices to remove invalid and unengaged email addresses.
- Content Optimization: Optimize email content to avoid spam trigger words and ensure a good text-to-image ratio.
- IP Address Warmup: Warm up the new IP address/sending domain by gradually increasing the volume of emails sent.
- Barracuda Monitoring and Mitigation: If recipients are behind Barracuda monitor the effectiveness with warming up the Barracuda domains slowly.
- Contact HubSpot and Barracuda Support: Consult with HubSpot support for deliverability best practices and contact Barracuda support to investigate domain blocks
What email marketers say
12 marketer opinions
High Barracuda bounce rates after migrating to HubSpot can stem from various factors, primarily related to sender reputation, email authentication, and content filtering. Barracuda's spam filters may block emails if the sending IP address has a poor reputation, especially when using shared IPs where other users might be sending spam. Shared domain blocking, or AWS IP range blocking by Barracuda could also be the cause. To resolve these issues, it's essential to check your sender reputation on blacklists, implement email authentication protocols (SPF, DKIM, DMARC), ensure email content is not flagged as spam (avoid spam trigger words, use proper HTML, maintain a good text-to-image ratio), clean up your email lists to remove inactive or invalid addresses, warm up your IP address by gradually increasing sending volume, monitor bounce rate benchmarks, and set up DMARC policies. Proper email list hygiene and engagement are also important.
Key opinions
- Sender Reputation: Poor sender reputation due to shared IPs or previous spam activity can lead to Barracuda blocking emails.
- Email Authentication: Lack of or improper SPF, DKIM, and DMARC records can cause authentication failures and higher bounce rates.
- Spam Content: Email content with spam trigger words, poor HTML coding, or a high image-to-text ratio can be flagged as spam.
- List Hygiene: Inactive or invalid email addresses in your list can increase bounce rates and negatively impact sender reputation.
- Shared Domain Issues: Hubspot's shared domains may be blocked by Barracuda due to activity by other users.
- Warmup needed: Starting with a new IP/ESP requires careful warmup to establish trust with receiving mail servers.
Key considerations
- Monitor Reputation: Regularly check your IP address and domain reputation on various blacklists and take corrective actions if needed.
- Implement Authentication: Configure SPF, DKIM, and DMARC records correctly to verify the authenticity of your emails.
- Optimize Content: Review your email content for spam trigger words, improve HTML coding, and ensure a good text-to-image ratio.
- Clean Email Lists: Regularly remove inactive or invalid email addresses to maintain a healthy email list.
- Warm Up IP Address: Gradually increase your sending volume when starting with a new IP address or ESP to establish a positive sending reputation.
- Monitor Bounce Rates: Track your bounce rates and compare them to industry averages to identify and address any deliverability issues.
- Consider Dedicated IP: If problems persist on shared IP, consider moving to a dedicated IP address and establish its reputation.
Marketer view
Email marketer from SendGrid shares that sender reputation is a crucial factor in email deliverability. They share that sender reputation is influenced by factors like bounce rates, spam complaints, and engagement metrics. Monitoring and maintaining a positive sender reputation is essential for ensuring that emails reach the inbox.
13 Nov 2021 - SendGrid
Marketer view
Email marketer from Litmus shares that understanding bounce rate benchmarks can help identify deliverability issues. A high bounce rate, especially after migrating to a new ESP, can indicate problems with your email list or sending practices. They recommend comparing your bounce rates to industry averages and investigating any significant deviations.
23 Oct 2021 - Litmus
What the experts say
6 expert opinions
After migrating to HubSpot, high Barracuda bounce rates can arise from several factors related to authentication thresholds, Barracuda's security checks, and the changes in your sending environment. Barracuda may block senders who exceed its score thresholds, with detailed rule information available in the Barracuda console. The opens and clicks may be automated clicks by Barracuda filtering. Monitoring bounce rates during migration is important for identifying technical issues, while maintaining good list hygiene ensures deliverability. Reputation and infrastructural issues must also be addressed to get your emails in the inbox.
Key opinions
- Authentication Thresholds: Bounces can occur if you exceed Barracuda's score thresholds, which are configurable within the Barracuda console.
- Barracuda Filtering: Barracuda may conduct security checks that mimic opens and clicks, and they may heavily filter emails from new sources.
- Migration Issues: Migrating to a new platform like HubSpot can introduce deliverability issues that require careful monitoring and attention.
- List Hygiene: Maintaining a healthy email list by focusing on engagement and address validity is essential for deliverability.
- Warmup Needed: After migrating, warming up the domain by slowly increasing the volume of emails sent is crucial for establishing a positive sending reputation.
Key considerations
- Monitor Bounce Rates: Pay close attention to your email bounce rate, especially when moving to a new platform, to identify technical or list problems.
- Improve Infrastructure and Reputation: When migrating, ensure that infrastructure and reputation are both set up correctly.
- Warmup Barracuda Domains: Consider warming up Barracuda domains slowly to avoid heavy filtering.
- Focus on Engagement: Prioritize engagement with your subscribers to improve deliverability and inbox placement.
Expert view
Expert from Email Geeks shares that if the recipients are behind Barracuda, recent opens and clicks could be from Barracuda checks on incoming mail. Barracuda might have identified a different sending source and are heavily filtering mail. To address the original question, there's no direct contact with Barracuda, but warming up the Barracuda domains slower is recommended.
21 Jul 2021 - Email Geeks
Expert view
Expert from Spam Resource explains that good list hygiene is about more than just removing old addresses, it is about focusing on the health and engagement of your subscribers to increase engagement rates, leading to improved deliverability and inbox placement.
4 Jun 2023 - Spam Resource
What the documentation says
5 technical articles
High Barracuda bounce rates after migrating to HubSpot can be attributed to various technical factors concerning sender authentication and reputation. Hard bounces significantly impact sender reputation and often stem from permanent issues like non-existent email addresses. Implementing SPF, DKIM, and DMARC is critical for verifying sender authenticity and avoiding spam filters. Barracuda uses Reputation Block Lists (RBLs) to filter spam, so being listed on an RBL can cause emails to be blocked or bounced. SPF records are crucial for specifying authorized IP addresses for sending emails on behalf of your domain, while DKIM uses cryptographic signatures to authenticate messages.
Key findings
- Bounce Types: High hard bounce rates negatively impact sender reputation.
- Authentication: SPF, DKIM, and DMARC are essential for verifying senders and preventing spam filters from blocking emails.
- Reputation Block Lists: Being listed on Barracuda's RBLs results in blocked or bounced emails.
- SPF Importance: SPF records define which IP addresses are authorized to send email for your domain.
- DKIM Authentication: DKIM uses cryptographic signatures to validate that a message truly came from the domain it claims.
Key considerations
- Address Hard Bounces: Address and remove hard bounces from your email list to maintain a good sender reputation.
- Implement Authentication Protocols: Setup and correctly configure SPF, DKIM, and DMARC to ensure email authenticity and avoid spam filters.
- Monitor RBL Listings: Regularly check if your IP address is listed on RBLs and take steps to remove it if necessary.
- Configure SPF Records: Set up accurate SPF records to specify authorized IP addresses for sending emails.
- Validate DKIM Settings: Ensure DKIM signing is correctly configured to authenticate your email messages.
Technical article
Documentation from HubSpot explains that bounces are categorized as either hard or soft. A hard bounce indicates a permanent reason an email cannot be delivered, such as a non-existent email address. Soft bounces are temporary issues. High bounce rates, especially hard bounces, negatively impact sender reputation. The documentation also details specific bounce codes and their meanings, which can help diagnose Barracuda-related bounce issues.
1 Mar 2022 - HubSpot
Technical article
Documentation from SparkPost explains that implementing sender authentication protocols like SPF, DKIM, and DMARC is crucial for improving email deliverability and avoiding spam filters. These protocols help verify that the sender is authorized to send emails on behalf of the domain. Incorrectly configured or missing authentication records can lead to higher bounce rates.
7 Jan 2023 - SparkPost
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