I'm not able to send build notification email from my jenkin server.
getting following error:

"Checking if email needs to be generated
Email was triggered for: Success
Sending email for trigger: Success
messageContentType = text/plain; charset=UTF-8
Collecting change authors...
build: 49
Adding recipients from trigger recipient list
Successfully created MimeMessage
An attempt to send an e-mail to empty list of recipients, ignored.
Some error occured trying to send the email...check the Jenkins log
Finished: SUCCESS"

Jenkins is installed on Mac OS . Current Jenkins version is 1.653 and Email Extension Plugin version is 2.47

I'm using smtp.gmail.com with port number 587 into email-ext config.

Please help to resolve this issue.