Invalid and or bounced email addresses

[bemall]

Scenario..a user inputs an incorrect email or fat fingers their email address. How can we capture and trap these invalid emails so that we can contact the user to enter the correct email address or correct it for them. Perhaps adding a field to forward all bounced emails to the email address in that filed. Scenario, a user is purchasing an item and goes through the quick checkout which requires that they enter an email address. They do so but they type the wrong letter or so. POSTMAN returns an invalid email address and that's it versus letting the application admin know that there is a bounced/invalid email that needs to be corrected. In this case the user will call the customer using the number on file or in certain cases, they can correct such addresses