13 Reasons Why Your Sendinblue SMTP Is Not Activated

When it comes to email marketing, Sendinblue stands as a popular choice for businesses due to its reliability and user-friendliness. However, sometimes users may encounter issues where their Sendinblue SMTP (Simple Mail Transfer Protocol) service is not activated. Here are thirteen potential reasons why this might occur:

1. Incorrect SMTP Settings

One of the most common reasons for SMTP not being activated is incorrect settings. This could include wrong server addresses, ports, or authentication details. Always double-check your SMTP settings against Sendinblue's official documentation.

2. Account Verification Pending

Before you can start sending emails via Sendinblue's SMTP, your account needs to be verified. If this process is not complete, your SMTP service may not be activated.

3. Credit Card Verification

If you're on a paid plan, your credit card details need to be verified. Any issues with payment or credit card validation can delay or prevent SMTP activation.

4. Domain Authentication

Sendinblue requires domain authentication to ensure email deliverability. If your domain is not properly authenticated, it can affect SMTP activation.

5. IP Address Blacklisting

If Sendinblue detects suspicious activity from your account, such as a sudden increase in email volume or a high bounce rate, it may blacklist your IP address, preventing SMTP activation.

6. Daily Sending Limit Reached

Sendinblue sets daily sending limits based on your account type. If you reach these limits, your SMTP service may be temporarily suspended.

7. Technical Issues on Sendinblue's Side

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Sometimes, technical glitches or server maintenance on Sendinblue's end can affect SMTP services. Checking Sendinblue's status page or contacting their support team can provide clarity.

8. Firewall or ISP Restrictions

Certain firewalls or ISPs may block SMTP ports, preventing you from activating the service. Check with your IT department or ISP for any such restrictions.

9. Incorrect DNS Records

Proper DNS records are crucial for email deliverability. Misconfigured DNS records can interrupt SMTP activation.

10. Software Conflicts

Software installed on your system, such as antivirus or firewall programs, may conflict with Sendinblue's SMTP settings.

11. Email Content Flags

If your email content triggers spam filters, it can affect your ability to send emails via SMTP. Ensure your content is compliant and doesn't contain spammy keywords.

12. Account Suspension

Violation of Sendinblue's terms of service can lead to account suspension, which would naturally prevent SMTP activation.

13. Outdated Software or Plugins

If you're using a plugin or integration to connect with Sendinblue, ensure it's up to date. Outdated software can cause compatibility issues.

In conclusion, there are various reasons why your Sendinblue SMTP might not be activated. Troubleshooting these issues often requires a systematic approach, checking each potential cause until the problem is resolved. Remember to always refer to Sendinblue's official documentation and, if necessary, reach out to their support team for assistance.