How to send an email using PHPMailer?

Question

PHP

There is google mail.
I use PHPMailer to send messages. Everything is OK, the letter is sent, the layout is beautiful, the sender - everything is fine.
However, there is a problem, the following icon is visible on the client side of the letter:

"The sender is confirmed. However, the letter came from the *domain name*.ru domain, which does not match the return address. "
I suspect that somewhere on the gmail side you need to pick DKIM, but this is completely dark forest and where to go, alas, I don’t know.
Please help with advice, where to dig?

Answer 1

https://github.com/PHPMailer/PHPMailer/blob/master...