title: How to change the security type from SSL to TLS in Jenkins?
body: <p>I am trying to setup the smtp email notification. I could see that the gmail part works fine. I want to configure it for my office 365. </p>
  
  <p>Smtp server = smtp.office365.com</p>
  
  <p>We don't have SSL configured. Instead we use TLS. How can I set the TLS in the Jenkins?
  There is only a check button which suggests to use SSL or not. If I disable it what is it going to use?</p>
  
  <p>I get the following errors -  </p>
  
  <pre><code>Failed to send out e-mail
  
  javax.mail.MessagingException: Could not connect to SMTP host: smtp.office365.com, port: 587;
    nested exception is:
      javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
      at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1934)
      at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:638)
      at javax.mail.Service.connect(Service.java:317)
      at javax.mail.Service.connect(Service.java:176)
      at javax.mail.Service.connect(Service.java:125)
      at javax.mail.Transport.send0(Transport.java:194)
      at javax.mail.Transport.send(Transport.java:124)
      at hudson.tasks.Mailer$DescriptorImpl.doSendTestMail(Mailer.java:499)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:616)
      at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:298)
      at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:161)
      at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:96)
      at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:120)
      at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
      at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:728)
      at org.kohsuke.stapler.Stapler.invoke(Stapler.java:858)
      at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:248)
      at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
      at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:728)
      at org.kohsuke.stapler.Stapler.invoke(Stapler.java:858)
      at org.kohsuke.stapler.Stapler.invoke(Stapler.java:631)
      at org.kohsuke.stapler.Stapler.service(Stapler.java:225)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
      at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:686)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1494)
      at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:96)
      at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:88)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)
      at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:48)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)
      at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
      at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
      at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)
      at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:46)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)
      at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1474)
      at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:499)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137)
      at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:533)
      at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
      at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1086)
      at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:428)
      at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
      at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1020)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
      at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)
      at org.eclipse.jetty.server.Server.handle(Server.java:370)
      at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:489)
      at org.eclipse.jetty.server.AbstractHttpConnection.content(AbstractHttpConnection.java:960)
      at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.content(AbstractHttpConnection.java:1021)
      at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:865)
      at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:240)
      at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:668)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:52)
      at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:679)
  Caused by: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
      at sun.security.ssl.InputRecord.handleUnknownRecord(InputRecord.java:542)
      at sun.security.ssl.InputRecord.read(InputRecord.java:374)
      at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:850)
      at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1190)
      at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1217)
      at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1201)
      at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:507)
      at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:238)
      at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1900)
      ... 63 more
  </code></pre>