The alert pop-up uses the cTrader email notification settings. First, you must configure your platform email notifications and then the alert pop-up email alert. To configure cTrader email notifications go to cTrader Settings => Email:
And then in Alert pop-up options => Email:
In Alert pop-up enter your sender (from) and recipient (to) email addresses, then change the email template according to your preferences by using the provided template keywords or by choosing the default template.
Once you are finished, after each alert trigger you will receive an email alert also.