Question2Answer Fatal Error - Could not sent email confirmation

Question

When user try to verify email, after tapping confirm button in mysite.com/confirm, it says-

Question2Answer fatal error:

Could not send email confirmation

Stack trace:

require() in index.php:27
require() in qa-index.php:188
qa_get_request_content() in qa-page.php:47
require() in page.php:183
qa_send_new_confirm() in confirm.php:62

how to solve it? please help him. Email confirmation code is not sending 

Comments

qa_send_new_confirm() invokes qa_send_notification() from the file qa-include/app/emails.php and returns the error if that function call fails. You need to debug what exactly in the called function goes wrong.

Also, what does the mail setup of that site even look like?