How do I use an external SMTP to send emails from Zoho Books?

You have the option to setup email relay servers to send emails from Zoho Books with custom SMTP. To do this:

• Go to Settings in the top right corner.
• Select Email Notifications under Reminders and Notifications.
• Navigate to the Email Relay section under Preferences in the left pane.
• Click + New Server.
• Enter the Server Name.
• Select the Port number.
• Enter the Daily Mail Limit.
• Select an option in the Use Secure Connection field.
• Select your Mail Delivery Preference.
• Choose your domain from the Domain in this Server field.
• If authentication is required, select Yes. If not, select No in the Authentication Required field.
• Click Save.

After setting up the email relay, you can enable the toggle next to it to send emails from Zoho Books.