Hi,

I have  a local jenkins user on rocket.chat

In global config ( https://jenkins/configure) when clicking on "Test connection" button, with my rocket.chat local user login & password ( no webhook used):

1. Success is print
2. No message in my test channel
3. here's the output in jenkins.log

   févr. 06, 2019 10:14:27 PM jenkins.plugins.rocketchatnotifier.rocket.RocketChatClientImpl sendSingleMessage
   GRAVE: Could not send message: Response{success=false, messages=null, message=null, users=null, user=null, channels=null, channel=null, info=null}
   févr. 06, 2019 10:14:27 PM jenkins.plugins.rocketchatnotifier.RocketClientImpl publish
   GRAVE: I/O error error during publishing message
   jenkins.plugins.rocketchatnotifier.rocket.errorhandling.RocketClientException: The send of the message was unsuccessful.
   	at jenkins.plugins.rocketchatnotifier.rocket.RocketChatClientImpl.sendSingleMessage(RocketChatClientImpl.java:167)
   	at jenkins.plugins.rocketchatnotifier.rocket.RocketChatClientImpl.send(RocketChatClientImpl.java:130)
   	at jenkins.plugins.rocketchatnotifier.RocketClientImpl.publish(RocketClientImpl.java:37)
   	at jenkins.plugins.rocketchatnotifier.RocketChatNotifier$DescriptorImpl.doTestConnection(RocketChatNotifier.java:589)
   	at java.lang.invoke.MethodHandle.invokeWithArguments(MethodHandle.java:627)
   	at org.kohsuke.stapler.Function$MethodFunction.invoke(Function.java:396)
   	at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:408)
   	at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:212)
   	at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:145)
   	at org.kohsuke.stapler.MetaClass$11.doDispatch(MetaClass.java:537)
   	at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)
   	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:739)
   	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:870)
   	at org.kohsuke.stapler.MetaClass$4.doDispatch(MetaClass.java:282)
   	at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)
   	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:739)
   	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:870)
   	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:668)
   	at org.kohsuke.stapler.Stapler.service(Stapler.java:238)
   	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
   	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:865)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1655)
   	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:154)
   	at hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:59)
   	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:151)
   	at jenkins.telemetry.impl.UserLanguages$AcceptLanguageFilter.doFilter(UserLanguages.java:128)
   	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:151)
   	at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:157)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
   	at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:64)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
   	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$1.doFilter(ChainedServletFilter.java:87)
   	at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:90)
   	at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
   	at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
   	at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:82)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
   	at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)
   	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
   	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533)
   	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146)
   	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:524)
   	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
   	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257)
   	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595)
   	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)
   	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1340)
   	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203)
   	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473)
   	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564)
   	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201)
   	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1242)
   	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144)
   	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
   	at org.eclipse.jetty.server.Server.handle(Server.java:503)
   	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:364)
   	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260)
   	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
   	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
   	at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118)
   	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)
   	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)
   	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)
   	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)
   	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)
   	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:765)
   	at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:683)
   	at java.lang.Thread.run(Thread.java:748)

It appears that my test channel was renamed and the name wasn't updated in jenkins.

But I think, the "test connection" should have failed