Odd because I can send test mails without issue. Why would that error show up below the Project Recipients List? I removed $DEFAULT_RECIPIENTS and did Apply and Save and now I don't see that error anymore.

If the field is not empty, there is a check done on the recipients list using the Mailer plugin.

So should I leave that filed empty if it's already defined in the Extended Email Notification Config? It seems that if there's something in the field, either a variable or a real email address, I get that error.

No, $DEFAULT_RECIPIENTS is correct for that field, but the AJAX check of the recipients will not work, so you should be able to just not worry about it. Though without the Mailer functioning correctly, you outgoing emails will not work. If you post a complete build log, perhaps it would help.

I can't give you the entire build log, but I can give you the relevant part at the end:

Retrieved Current Release Current Release
Renaming Current Release to Release 84 and marking it as released
Updating current version with the following attributes:

Creating new version
Email was triggered for: Success
Sending email for trigger: Success

Also I found in the Jenkins System Log the following:

Aug 07, 2013 4:45:40 AM SEVERE winstone.Logger logInternal
Error while serving http://jenkins.fitbit.com/publisher/ExtendedEmailPublisher/recipientListRecipientsCheck
java.lang.reflect.InvocationTargetException
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:297)
at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:160)
at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:95)
at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:111)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:684)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:777)
at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:239)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:684)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:777)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:586)
at org.kohsuke.stapler.Stapler.service(Stapler.java:217)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:248)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:376)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:96)
at hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:58)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:99)
at hudson.plugins.audit_trail.AuditTrailFilter.doFilter(AuditTrailFilter.java:66)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:99)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:88)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:48)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
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 org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:174)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at jenkins.security.ApiTokenFilter.doFilter(ApiTokenFilter.java:64)
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$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:47)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:331)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:227)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
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: java.lang.NoClassDefFoundError: hudson/tasks/Mailer
at hudson.plugins.emailext.EmailRecipientUtils.convertRecipientString(EmailRecipientUtils.java:40)
at hudson.plugins.emailext.EmailRecipientUtils.validateFormRecipientList(EmailRecipientUtils.java:105)
at hudson.plugins.emailext.ExtendedEmailPublisherDescriptor.doRecipientListRecipientsCheck(ExtendedEmailPublisherDescriptor.java:442)
... 70 more

Second that – a success event is logged, but no e-mails are sent. In fact, it is worse than not sending the e-mails. Since upgrading Jenkins to 1.526 (extmail at 2.30.2), an exception thrown from within the plugin is propagating all the way up and prevents Jenkins from updating the "last success/failure" build counters. The dashboard is already a number of builds behind the actual ones.

Updated: the exception is gone, the success/failure build counters are fine, and e-mail is working again after downgrading Jenkins to 1.523.

In my case, the log looked like this:

Executor threw an exception
java.lang.NoClassDefFoundError: org/sonatype/aether/util/StringUtils
at hudson.plugins.emailext.plugins.content.ChangesSinceLastBuildContent.evaluate(ChangesSinceLastBuildContent.java:56)
at hudson.plugins.emailext.plugins.content.AbstractChangesSinceContent$1.printSpec(AbstractChangesSinceContent.java:102)
at hudson.plugins.emailext.Util.printf(Util.java:91)
at hudson.plugins.emailext.plugins.content.AbstractChangesSinceContent.appendBuild(AbstractChangesSinceContent.java:97)
at hudson.plugins.emailext.plugins.content.AbstractChangesSinceContent.evaluate(AbstractChangesSinceContent.java:84)
at org.jenkinsci.plugins.tokenmacro.DataBoundTokenMacro.evaluate(DataBoundTokenMacro.java:177)
at org.jenkinsci.plugins.tokenmacro.TokenMacro.expand(TokenMacro.java:182)
at org.jenkinsci.plugins.tokenmacro.TokenMacro.expandAll(TokenMacro.java:233)
at hudson.plugins.emailext.plugins.ContentBuilder.transformText(ContentBuilder.java:63)
at hudson.plugins.emailext.ExtendedEmailPublisher.getContent(ExtendedEmailPublisher.java:705)
at hudson.plugins.emailext.ExtendedEmailPublisher.createMail(ExtendedEmailPublisher.java:488)
at hudson.plugins.emailext.ExtendedEmailPublisher.sendMail(ExtendedEmailPublisher.java:319)
at hudson.plugins.emailext.ExtendedEmailPublisher._perform(ExtendedEmailPublisher.java:311)
at hudson.plugins.emailext.ExtendedEmailPublisher.perform(ExtendedEmailPublisher.java:271)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:36)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:804)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:776)
at hudson.model.Build$BuildExecution.cleanUp(Build.java:192)
at hudson.model.Run.execute(Run.java:1642)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:247)

email-ext is NOT tested with the latest versions of Jenkins, it is tested with the most recent LTS, so if you install a newer Jenkins version than the LTS, you could definitely run into issues.

We need to be using at least version 1.524 as this fixes a critical bug with clock differences on slaves. Any way you can test your plugin with that version?

Not without some significant work, most plugin developers only support the latest LTS, unless their plugin requires some features of newer versions of Jenkins. I could run the test suite against a newer version, but fixing bugs against a newer version is not as easy depending on what the issues are. I'll try and run the test suite and see if anything pops up that is low hanging fruit.

Thanks! Really appreciate it.

Yes I also confirm that downgrading to 1.523 fixes the issue and notification mails are now sent.

I ran the test suite with 1.526 and it didn't flag any major issues.

I tried both 1.524 and 1.526 and both have the same issue of not sending mail.

I think these two might be one and the same.

I can confirm I'm seeing the same issues with both 1.524 and 1.526.

seems to be fixed by: https://github.com/jenkinsci/email-ext-plugin/commit/42f57cbd0c1e80f90cfce2f3f13ce996c75ceb25

plans for a new version that includes it ?

Yes, should be soon.

excellent! thanks for the super fast response

manually uploaded https://buildhive.cloudbees.com/job/jenkinsci/job/email-ext-plugin/org.jenkins-ci.plugins$email-ext/178/ and problem is gone

Is the updated plugin ready?

The manual plugin did not work for me. I've had to downgrade to 1.523 to get e-mail to send.

Don't use the manual plugin, use the version that was released (2.32). Also, please provide more information if it didn't work for you.

Well, given that I had just installed the plugin for the first time today, I can probably confirm that 2.32 also didn't work. I got the exact behavior detailed earlier in this thread - if the new plugin had worked, I wouldn't have had to go searching for bug reports in the first place.

"The manual plugin did not work for me. I've had to downgrade to 1.523 to get e-mail to send." The manual plugin is not 2.32, it was a snapshot of it that was installed manually from the build system, not the update center. Please detail your setup if you are having issues still.

0) I installed Jenkins 1.528.
1) I installed the plugin automatically from the Jenkins plugin list. We can assume this was 2.32 since I just did it last night, right?
2) I got the exact errors detailed in this bug report.
3) Only then did I install 2.30-SNAPSHOT, without noticing that it was a lower version than the current plugin.

Unless there's some way I could have automatically installed an outdated plugin in 1), I am declaring my problem still extant.

Then please post your build log, and list of enabled plugins.

Building in workspace /var/lib/jenkins/jobs/test/workspace
No emails were triggered.
Email was triggered for: Success
Sending email for trigger: Success
Sending email to: [redacted]
Finished: SUCCESS

No e-mail was received. The mailer and mail-ext plugins were enabled. I'm not aware of a convenient way to post a screen shot of my enabled plugins, and enumerating them seems pointless unless there's some known issue with some other plugin interacting with the mail plugins, specifically on Jenkins 1.524-1.528.

Please also post any exceptions seen in the Jenkins logs.

I still see the following error on Jenkins 1.528

Aug 23, 2013 4:08:30 PM SEVERE winstone.Logger logInternal
Error while serving http://localhost:8080/publisher/ExtendedEmailPublisher/recipientListRecipientsCheck
java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor643.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:297)
at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:160)
at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:95)
at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:111)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:685)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:799)
at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:239)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:685)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:799)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:587)
at org.kohsuke.stapler.Stapler.service(Stapler.java:218)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:248)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:376)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:96)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:88)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:48)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
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 org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:174)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at jenkins.security.ApiTokenFilter.doFilter(ApiTokenFilter.java:64)
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$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:46)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:331)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:227)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoClassDefFoundError: hudson/tasks/Mailer
at hudson.plugins.emailext.EmailRecipientUtils.convertRecipientString(EmailRecipientUtils.java:40)
at hudson.plugins.emailext.EmailRecipientUtils.validateFormRecipientList(EmailRecipientUtils.java:105)
at hudson.plugins.emailext.ExtendedEmailPublisherDescriptor.doRecipientListRecipientsCheck(ExtendedEmailPublisherDescriptor.java:428)
... 65 more

Here is the end of the build log:

Checking console output
Run condition [Text Finder] preventing perform for step [Set the build result]
Archiving artifacts
Recording NUnit tests results
Email was triggered for: Success
Sending email for trigger: Success

Here is a screenshot of all the installed plugins.

I hadn't gotten a chance to roll back (forward) to 1.528, but that's more or less what I recall seeing in that configuration.

The mail is still not sending or you just see the error in the gui when configuring the job?

Mail is still not sending.

There are no exceptions in the Jenkins logs? When do you see that exception?

The one I posted is from the Jenkins log. There are no email exceptions in build log.

Can you enable debug mode in the global config and then post the build log?

Here is the end of the build log with debug enabled:

Run condition [Text Finder] preventing perform for step [Set the build result]
Archiving artifacts
Recording NUnit tests results
Checking for post-build
Performing post-build step
Checking if email needs to be generated
Email was triggered for: Success
Sending email for trigger: Success
NOT overriding default server settings, using Mailer to create session

Here is the end of the Jenkins log for the last little bit:

Aug 23, 2013 4:24:30 PM SEVERE hudson.model.Executor run
Executor threw an exception
java.lang.NoClassDefFoundError: hudson/tasks/Mailer
at hudson.plugins.emailext.ExtendedEmailPublisher.createMail(ExtendedEmailPublisher.java:412)
at hudson.plugins.emailext.ExtendedEmailPublisher.sendMail(ExtendedEmailPublisher.java:269)
at hudson.plugins.emailext.ExtendedEmailPublisher._perform(ExtendedEmailPublisher.java:261)
at hudson.plugins.emailext.ExtendedEmailPublisher.perform(ExtendedEmailPublisher.java:221)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:45)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:804)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:776)
at hudson.model.Build$BuildExecution.cleanUp(Build.java:192)
at hudson.model.Run.execute(Run.java:1648)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:247)

Aug 23, 2013 4:26:24 PM INFO hudson.model.Run execute
XactPRM Online - Test 0.2.221 main build action completed: SUCCESS
Aug 23, 2013 4:26:24 PM SEVERE hudson.model.Executor run
Executor threw an exception
java.lang.NoClassDefFoundError: hudson/tasks/Mailer
at hudson.plugins.emailext.ExtendedEmailPublisher.createMail(ExtendedEmailPublisher.java:412)
at hudson.plugins.emailext.ExtendedEmailPublisher.sendMail(ExtendedEmailPublisher.java:269)
at hudson.plugins.emailext.ExtendedEmailPublisher._perform(ExtendedEmailPublisher.java:261)
at hudson.plugins.emailext.ExtendedEmailPublisher.perform(ExtendedEmailPublisher.java:221)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:45)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:804)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:776)
at hudson.model.Build$BuildExecution.cleanUp(Build.java:192)
at hudson.model.Run.execute(Run.java:1648)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:247)

Aug 23, 2013 4:27:47 PM INFO hudson.model.DownloadService$Downloadable doPostBack
Obtained the updated data file for hudson.tasks.Maven.MavenInstaller
Aug 23, 2013 4:27:47 PM INFO hudson.model.DownloadService$Downloadable doPostBack
Obtained the updated data file for hudson.tools.JDKInstaller
Aug 23, 2013 4:27:48 PM INFO hudson.model.UpdateSite updateData
Obtained the latest update center data file for UpdateSource default
Aug 23, 2013 4:31:23 PM INFO hudson.model.AsyncPeriodicWork$1 run
Started Out of order build detection
Aug 23, 2013 4:31:54 PM WARNING jenkins.diagnostics.ooom.Problem$Inspector scan
Failed to inspect C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Stage\builds\2013-07-16_17-02-06: C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Stage\builds\2013-07-16_17-02-06\build.xml doesn't exist
Aug 23, 2013 4:31:54 PM WARNING jenkins.diagnostics.ooom.Problem$Inspector scan
Failed to inspect C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Stage\builds\22: C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Stage\builds\22\build.xml doesn't exist
Aug 23, 2013 4:32:04 PM WARNING jenkins.diagnostics.ooom.Problem$Inspector scan
Failed to inspect C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Test\builds\2013-06-26_09-18-51: C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Test\builds\2013-06-26_09-18-51\build.xml doesn't exist
Aug 23, 2013 4:32:04 PM WARNING jenkins.diagnostics.ooom.Problem$Inspector scan
Failed to inspect C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Test\builds\22: C:\Program Files (x86)\Jenkins\jobs\XactPRM Online - Test\builds\22\build.xml doesn't exist
Aug 23, 2013 4:32:25 PM INFO hudson.model.AsyncPeriodicWork$1 run
Finished Out of order build detection. 61498 ms
Aug 23, 2013 11:55:54 PM INFO hudson.model.AsyncPeriodicWork$1 run
Started Workspace clean-up
Aug 23, 2013 11:55:54 PM INFO hudson.model.AsyncPeriodicWork$1 run
Finished Workspace clean-up. 0 ms
Aug 24, 2013 8:53:08 AM INFO hudson.model.Run execute
XactPRM Online - Test 0.2.222 main build action completed: SUCCESS
Aug 24, 2013 8:53:08 AM SEVERE hudson.model.Executor run
Executor threw an exception
java.lang.NoClassDefFoundError: hudson/tasks/Mailer
at hudson.plugins.emailext.ExtendedEmailPublisher.createMail(ExtendedEmailPublisher.java:412)
at hudson.plugins.emailext.ExtendedEmailPublisher.sendMail(ExtendedEmailPublisher.java:269)
at hudson.plugins.emailext.ExtendedEmailPublisher._perform(ExtendedEmailPublisher.java:261)
at hudson.plugins.emailext.ExtendedEmailPublisher.perform(ExtendedEmailPublisher.java:221)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:45)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:804)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:776)
at hudson.model.Build$BuildExecution.cleanUp(Build.java:192)
at hudson.model.Run.execute(Run.java:1648)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:247)

Something must be messed up with the install of the mailer plugin, I don't have any other answer to why this is happening.

Can you try accessing the Mailer plugin from the script console to see its available?

I blew away the install of Jenkins and rebuilt it. It seems to be working now.

Ok, glad it's working, but that doesn't help solve the issue

i'm also seeing this problem exact same symptoms and results.

would love to know how to resolve!

Try uninstalling and re-installing the Mailer plugin. With the normal restart of Jenkins in between.

The "Mailer" plugin doesn't have an uninstall option from what I can see. Do you mean the email-ext plugin?

No, you have to "unpin" and then you can uninstall it. Also, what versions of Jenkins, Mailer and email-ext are you using?

Jenkins 1.529
Mailer 1.5
email-ext 2.32

I unpinned Mailer and refreshed the plugins screen, still don't see an uninstall option?

http://screencast.com/t/Di7RZLp30Ttj

Strange...I thought you could uninstall once you unpin. If you are feeling adventurous, shutdown Jenkins, remove the mailer directory under $JENKINS_HOME/plugins as well as the jpi/hpi and then try re-installing.

Can you try downgrading to 1.4?

I downgraded email-ext to 2.27.1 and now I'm seeing build emails again.

Have you tried any version in between 2.32 and 2.27.1?

No I haven't. That was the version presented as a downgrade option in the manage plugins page.

If you're still feeling adventurous, can you try installing the snapshot for 2.33 from here: https://buildhive.cloudbees.com/job/jenkinsci/job/email-ext-plugin/188/org.jenkins-ci.plugins$email-ext/