Jackytran

Thank you.
I will wait for the correct way to solve the problem of my site in version 3.6.1. I hope everyone can have a right solution soon.
Now I will send password to new registration manually.
If anyone can have a right solution for version 3.6.1, please help.
Thank you again.

Thank you, Bob.
It maybe because I’m using 3.6.1 version wordpress. I have found other people have the same problem and cannot fix it by your way.
How can I downgrade to 3.6?

Me too. I have the same problem with 3.6.1 verson. Now I cannot do anything.
Any one can help?

Help me again.
I have downloaded the 5.2.6 and unzip it. And then I have upload 3 files class.phpmailer.php, class.pop3.php and class.smtp.php to my host.
And then I try 3 ways,
First, rename class.phpmailer.php to class-phpmailer.php and replace the current file. It not work.
Second, rename class.phpmailer.php, class.pop3.php and class.smtp.php to class-phpmailer.php, class-pop3.php and class-smtp.php and replace the current files. It not work.
Third, delete class-phpmailer.php, class-pop3.php and class-smtp.php, and then upload class.phpmailer.php, class.pop3.php and class.smtp.php version 5.2.6. It still not work.
Did I do anything wrong?
And now I dont know how to correct the problem. Now I’m keeping 3 files class.phpmailer.php, class.pop3.php and class.smtp.php on my host. You can try to test it via https://vi.vnlgbt.com/wp-admin.
Thank you for your help.

Help me
I have updated the class-phpmailer.php from version 5.2.4 to 5.2.7 and also downgrade to 5.2.1, and then now I re-updated to 5.2.7 version, but the problem is still there, my wordpress still not send registration email.
Please help.
My client wordpress site is https://vi.vnlgbt.com. Im using godaddy host and email.
Thank you