Sendinblue not work

Hi @mario-barretta,

Thanks for reaching out! According to the error message, most probably you may have copied some part of your API key like this, which is invalid.

Please head over to the following link (https://account.sendinblue.com/advanced/api), delete your existing API key (see: https://a.supportally.com/ZYACHs). Then add a new API key and copy the full key like this.

Also, you need to authorize your domain by adding Sendinblue DNS records by following our guide here (https://wpmailsmtp.com/docs/how-to-set-up-the-sendinblue-mailer-in-wp-mail-smtp/#authorize-domain).

Once you complete those steps, try sending a test email (WP Mail SMTP -> Tools) and it should work.

I hope this helps. Thanks!