WordPress was update to 3.9 version last week. But I found the SMTP could not work in this WordPress version.
I used the SMTP to sent the E-Mail to notice my reader. And I can recieved the pushmail at the same time. So I could reply the comment in time. This bug cause a lot of trouble for me.
So I viewed the source codes of WordPress 3.9. The WordPress 3.9 used the newer PHPMailer module. As a result, the SMTP colud not connect.
So, We can replace the PHPMailer to the old version to slove this problem. Just download the file which I supported, and unpack it to replace the file in /wp-includes. After it, try to sent the test E-Mail.
Enjoy WordPress and have a nice day .
The old version of PHPMailer：
fix-20140422(My website server): Download