Unable to send mail through Jenkins Getting Exception

[Neeraj Bakhtani]

HI Friends,
I am trying to setup Email Notification in Jenkins

But When I click on Test Configuration , I am getting below error

Refer Attached Screenshot as well as below Error

Pls Help I am stuck here.

sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

	at sun.security.provider.certpath.SunCertPathBuilder.build(Unknown Source)

	at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(Unknown Source)

	at java.security.cert.CertPathBuilder.build(Unknown Source)

Caused: sun.security.validator.ValidatorException: PKIX path building failed

	at sun.security.validator.PKIXValidator.doBuild(Unknown Source)

	at sun.security.validator.PKIXValidator.engineValidate(Unknown Source)

	at sun.security.validator.Validator.validate(Unknown Source)

	at sun.security.ssl.X509TrustManagerImpl.validate(Unknown Source)

	at sun.security.ssl.X509TrustManagerImpl.checkTrusted(Unknown Source)

	at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(Unknown Source)

Caused: javax.net.ssl.SSLHandshakeException

	at sun.security.ssl.Alerts.getSSLException(Unknown Source)

	at sun.security.ssl.SSLSocketImpl.fatal(Unknown Source)

	at sun.security.ssl.Handshaker.fatalSE(Unknown Source)

	at sun.security.ssl.Handshaker.fatalSE(Unknown Source)

	at sun.security.ssl.ClientHandshaker.serverCertificate(Unknown Source)

	at sun.security.ssl.ClientHandshaker.processMessage(Unknown Source)

	at sun.security.ssl.Handshaker.processLoop(Unknown Source)

	at sun.security.ssl.Handshaker.process_record(Unknown Source)

	at sun.security.ssl.SSLSocketImpl.readRecord(Unknown Source)

	at sun.security.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)

	at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)

	at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)

	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)

Caused: javax.mail.MessagingException: Could not connect to SMTP host: smtp.gmail.com, port: 465;
  nested exception is:
	javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

	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:581)

	at java.lang.invoke.MethodHandle.invokeWithArguments(Unknown Source)

	at org.kohsuke.stapler.Function$MethodFunction.invoke(Function.java:343)

	at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:184)

	at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:117)

	at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:129)

	at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)

	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:715)

	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:845)

	at org.kohsuke.stapler.MetaClass$5.doDispatch(MetaClass.java:248)

	at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)

	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:715)

	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:845)

	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:649)

	at org.kohsuke.stapler.Stapler.service(Stapler.java:238)

	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)

	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:841)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:135)

	at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:138)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637)

	at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:49)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637)

	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)

	at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:90)

	at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637)

	at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637)

	at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:82)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637)

	at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)

	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637)

	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533)

	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)

	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:524)

	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)

	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:190)

	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595)

	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:188)

	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1253)

	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:168)

	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473)

	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564)

	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:166)

	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1155)

	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)

	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)

	at org.eclipse.jetty.server.Server.handle(Server.java:564)

	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:317)

	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251)

	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:279)

	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:110)

	at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:124)

	at org.eclipse.jetty.util.thread.Invocable.invokePreferred(Invocable.java:128)

	at org.eclipse.jetty.util.thread.Invocable$InvocableExecutor.invoke(Invocable.java:222)

	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:294)

	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:199)

	at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)

	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)

	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)

	at java.lang.Thread.run(Unknown Source)