Brevo

Unrecognized IP address

When sending emails through YaySMTP using Brevo (SMTP), you may encounter a failed email log with the following error:

[401]: We have detected you are using an unrecognised IP address.
If you performed this action make sure to add the new IP address.

Error overview

This happens when Brevo blocks the SMTP request because the server’s IP address has not been authorized in your Brevo security settings.

The error will appear in YaySMTP → Email Logs when viewing a failed email.

Typical indicators:

• Email status: Failed

• Mailer: Brevo

• Error code: 401

• Message mentions “unrecognised IP address”

How to fix it

1️⃣ Identify the IP address

Go to: WordPress → YaySMTP → Email Logs

Open the failed email and locate the IP address mentioned in the error message.

2️⃣ Add or authorize the IP address

1. Log in to your Brevo Dashboard

2. Find the Authorized IPs section or click this link: https://app.brevo.com/security/authorised_ips

3. Click Add a new IP address

4. Paste the IP address you copied from the YaySMTP error log

5. Save the changes

3️⃣ Check unauthorized IPs (optional)

Sometimes an IP address may appear in both lists in Brevo.

If the IP exists in the Unauthorized IP addresses list, Brevo will still treat it as unauthorized, even if it also appears in the Authorized list.

In that case, email sending will still fail.

Here, make sure the IP address:

• ✅ Appears in the "Authorized IP addresses" tab

• ❌ Does NOT appear in the "Unauthorized IP addresses" tab

4️⃣ Test email again

Return to your WordPress dashboard > YaySMTP, and send a test email to verify that the issue has been resolved.