Hey @c4rboff,
Thank you for reaching out! There are a few issues that trigger that particular error message.
Firstly, please make sure that you’ve completed all information in SliceWP > Settings > Email Notifications (tab). This includes the From Email, From Name, Admin Emails fields, alongside the Email Subject and Email Content for all email notifications.
If you have this information all set up, but you’re still seeing the error, please make sure that your WordPress website is sending emails. You can verify this by trying to reset your password via the WordPress wp-admin page (while being logged out).
Also, I recommend following our email notifications troubleshooting guide here: https://slicewp.com/docs/emails-not-being-sent/
Thank you and best wishes,
Mihai