javax.net.ssl.SSLException when sending mail using JavaMail

Question

javax.mail.MessagingException: Exception reading response;
  nested exception is:
        javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
        at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1764)
        at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1523)
        at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:453)
        at javax.mail.Service.connect(Service.java:313)
        at javax.mail.Service.connect(Service.java:172)
        at javax.mail.Service.connect(Service.java:121)
        at javax.mail.Transport.send0(Transport.java:190)
        at javax.mail.Transport.send(Transport.java:120)
        at javaapplication5.SendMail.send(SendMail.java:77)
        at javaapplication5.SendMailTest.main(SendMailTest.java:17)
Caused by: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
        at com.sun.net.ssl.internal.ssl.InputRecord.handleUnknownRecord(InputRecord.java:523)
        at com.sun.net.ssl.internal.ssl.InputRecord.read(InputRecord.java:355)
        at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:789)
        at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1112)
        at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:744)
        at com.sun.net.ssl.internal.ssl.AppInputStream.read(AppInputStream.java:75)
        at com.sun.mail.util.TraceInputStream.read(TraceInputStream.java:106)
        at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:237)
        at com.sun.mail.util.LineInputStream.readLine(LineInputStream.java:84)
        at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1742)
        ... 9 more

Can anybody help me to send a mail using JavaMail API using proxy?

Answer 1

You are trying to do an SSL connection to a non-SSL port. This will not work.

If you want to send mail through gmail, see the FAQ: http://java.sun.com/products/javamail/FAQ.html#gmail

Answer 2

I was getting the same exception when trying to send email via the Hotmail SMTP server at smtp.live.com. Here are the settings that worked for me in the end:

mail.smtp.starttls.enable=true 
mail.smtp.port=587