Failed to instantiate class hudson.plugins.emailext.ExtendedEmailPublisher

javax.servlet.ServletException: java.lang.RuntimeException: Failed to instantiate class hudson.plugins.emailext.ExtendedEmailPublisher from {"project_disabled":false,"project_recipient_list":"$DEFAULT_RECIPIENTS","project_replyto":"$DEFAULT_REPLYTO","project_content_type":"default","project_default_subject":"$DEFAULT_SUBJECT","project_default_content":"$DEFAULT_CONTENT","project_attachments":"","project_attach_buildlog":"0","project_presend_script":"$DEFAULT_PRESEND_SCRIPT","project_save_output":false,"project_triggers":

{"stapler-class":"","$class":""}

,"stapler-class":"hudson.plugins.emailext.ExtendedEmailPublisher","$class":"hudson.plugins.emailext.ExtendedEmailPublisher"}
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:796)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:249)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:649)
at org.kohsuke.stapler.Stapler.service(Stapler.java:238)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:686)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1494)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:123)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:114)
at org.eclipse.jetty.servlet.ServletHandler$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.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at jenkins.security.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:117)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at jenkins.security.BasicHeaderProcessor.doFilter(BasicHeaderProcessor.java:93)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:67)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)
at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)
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:1482)
at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)
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:235)
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$1.run(BoundedExecutorService.java:77)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.RuntimeException: Failed to instantiate class hudson.plugins.emailext.ExtendedEmailPublisher from {"project_disabled":false,"project_recipient_list":"$DEFAULT_RECIPIENTS","project_replyto":"$DEFAULT_REPLYTO","project_content_type":"default","project_default_subject":"$DEFAULT_SUBJECT","project_default_content":"$DEFAULT_CONTENT","project_attachments":"","project_attach_buildlog":"0","project_presend_script":"$DEFAULT_PRESEND_SCRIPT","project_save_output":false,"project_triggers":

{"stapler-class":"","$class":""}

,"stapler-class":"hudson.plugins.emailext.ExtendedEmailPublisher","$class":"hudson.plugins.emailext.ExtendedEmailPublisher"}
at hudson.model.Descriptor.newInstance(Descriptor.java:579)
at hudson.model.Descriptor.newInstancesFromHeteroList(Descriptor.java:929)
at hudson.model.Descriptor.newInstancesFromHeteroList(Descriptor.java:903)
at hudson.util.DescribableList.rebuildHetero(DescribableList.java:208)
at hudson.maven.MavenModuleSet.submit(MavenModuleSet.java:1208)
at hudson.model.Job.doConfigSubmit(Job.java:1206)
at hudson.model.AbstractProject.doConfigSubmit(AbstractProject.java:788)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.kohsuke.stapler.Function$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$1.doDispatch(MetaClass.java:121)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
... 63 more
Caused by: java.lang.IllegalArgumentException: Failed to instantiate class hudson.plugins.emailext.ExtendedEmailPublisher from {"project_disabled":false,"project_recipient_list":"$DEFAULT_RECIPIENTS","project_replyto":"$DEFAULT_REPLYTO","project_content_type":"default","project_default_subject":"$DEFAULT_SUBJECT","project_default_content":"$DEFAULT_CONTENT","project_attachments":"","project_attach_buildlog":"0","project_presend_script":"$DEFAULT_PRESEND_SCRIPT","project_save_output":false,"project_triggers":

{"stapler-class":"","$class":""}

,"stapler-class":"hudson.plugins.emailext.ExtendedEmailPublisher","$class":"hudson.plugins.emailext.ExtendedEmailPublisher"}
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:602)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:404)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:400)
at hudson.model.Descriptor.newInstance(Descriptor.java:570)
... 79 more
Caused by: java.lang.IllegalArgumentException: Failed to convert the project_triggers parameter of the constructor public hudson.plugins.emailext.ExtendedEmailPublisher(java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,int,java.lang.String,boolean,java.util.List,hudson.plugins.emailext.MatrixTriggerMode,boolean,java.util.List)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:699)
at org.kohsuke.stapler.RequestImpl.access$200(RequestImpl.java:81)
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:600)
... 82 more
Caused by: java.lang.IllegalArgumentException: Failed to instantiate class hudson.plugins.emailext.plugins.EmailTrigger from

{"stapler-class":"","$class":""}

at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:602)
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:638)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:404)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:697)
... 84 more
Caused by: java.lang.IllegalArgumentException: Class is specified in JSON, but no such class found in classLoader hudson.PluginManager$UberClassLoader
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:596)
... 87 more
Caused by: java.lang.ClassNotFoundException: cached miss for
at hudson.PluginManager$UberClassLoader.findClass(PluginManager.java:1105)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:591)
... 87 more