The SMTP test connection is not working

[M Shaikh]

I'm getting this error when sending test mail.

An error has occurred with sending the test email:
com.atlassian.mail.MailException: javax.mail.MessagingException: Exception reading response;
  nested exception is:
    java.net.SocketException: Connection reset
    at com.atlassian.mail.server.impl.SMTPMailServerImpl.send(SMTPMailServerImpl.java:193)
    at com.atlassian.jira.plugins.mail.webwork.SendTestMail.doExecute(SendTestMail.java:107)
    at webwork.action.ActionSupport.execute(ActionSupport.java:165)
    at com.atlassian.jira.action.JiraActionSupport.execute(JiraActionSupport.java:82)
    at webwork.interceptor.DefaultInterceptorChain.proceed(DefaultInterceptorChain.java:39)
    at webwork.interceptor.NestedInterceptorChain.proceed(NestedInterceptorChain.java:31)
    at webwork.interceptor.ChainedInterceptor.intercept(ChainedInterceptor.java:16)
    at webwork.interceptor.DefaultInterceptorChain.proceed(DefaultInterceptorChain.java:35)
    at webwork.dispatcher.GenericDispatcher.executeAction(GenericDispatcher.java:221)
    at webwork.dispatcher.GenericDispatcher.executeAction(GenericDispatcher.java:150)
    at com.atlassian.jira.web.dispatcher.JiraWebworkActionDispatcher.service(JiraWebworkActionDispatcher.java:153)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.web.filters.steps.ChainedFilterStepRunner.doFilter(ChainedFilterStepRunner.java:78)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.core.filters.HeaderSanitisingFilter.doFilter(HeaderSanitisingFilter.java:44)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.bugdigger.plugins.BugDiggerServletFilter.doFilter(Unknown Source)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.labs.botkiller.BotKillerFilter.doFilter(BotKillerFilter.java:36)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.jira.tzdetect.IncludeResourcesFilter.doFilter(IncludeResourcesFilter.java:39)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:25)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:77)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:63)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.web.filters.accesslog.AccessLogFilter.executeRequest(AccessLogFilter.java:103)
    at com.atlassian.jira.web.filters.accesslog.AccessLogFilter.doFilter(AccessLogFilter.java:87)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.security.xsrf.XsrfTokenAdditionRequestFilter.doFilter(XsrfTokenAdditionRequestFilter.java:54)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
    at com.atlassian.jira.web.filters.SitemeshPageFilter.doFilter(SitemeshPageFilter.java:124)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.labs.remoteapps.modules.permissions.ApiScopingFilter.doFilter(ApiScopingFilter.java:71)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:77)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:63)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:234)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.security.auth.trustedapps.filter.TrustedApplicationsFilter.doFilter(TrustedApplicationsFilter.java:98)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.seraph.filter.BaseLoginFilter.doFilter(BaseLoginFilter.java:157)
    at com.atlassian.jira.web.filters.JiraLoginFilter.doFilter(JiraLoginFilter.java:70)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.oauth.serviceprovider.internal.servlet.OAuthFilter.doFilter(OAuthFilter.java:71)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.bonfire.web.filters.BonfireP3PFilter.doFilter(BonfireP3PFilter.java:57)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:77)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:63)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:99)
    at com.atlassian.jira.web.filters.JIRAProfilingFilter.doFilter(JIRAProfilingFilter.java:19)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.johnson.filters.AbstractJohnsonFilter.doFilter(AbstractJohnsonFilter.java:71)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:738)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.gzipfilter.GzipFilter.doFilterInternal(GzipFilter.java:80)
    at com.atlassian.gzipfilter.GzipFilter.doFilter(GzipFilter.java:51)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.atlassian.labs.remoteapps.modules.oauth.OAuth2LOFilter.doFilter(OAuth2LOFilter.java:70)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
    at com.sysbliss.jira.plugins.workflow.servlet.JWDSendRedirectFilter.doFilter(JWDSendRedirectFilter.java:25)
    at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
    at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:77)
    at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:63)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.web.filters.steps.ChainedFilterStepRunner.doFilter(ChainedFilterStepRunner.java:78)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.core.filters.cache.AbstractCachingFilter.doFilter(AbstractCachingFilter.java:33)
    at com.atlassian.core.filters.AbstractHttpFilter.doFilter(AbstractHttpFilter.java:31)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.core.filters.encoding.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:41)
    at com.atlassian.core.filters.AbstractHttpFilter.doFilter(AbstractHttpFilter.java:31)
    at com.atlassian.jira.web.filters.PathMatchingEncodingFilter.doFilter(PathMatchingEncodingFilter.java:49)
    at com.atlassian.core.filters.AbstractHttpFilter.doFilter(AbstractHttpFilter.java:31)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.web.monitor.ActiveRequestsFilter$PassToChainFilterFunc.doFilter(ActiveRequestsFilter.java:346)
    at com.atlassian.jira.web.monitor.ActiveRequestsFilter$DebugLogFilterFunc.doFilter(ActiveRequestsFilter.java:463)
    at com.atlassian.jira.web.monitor.ActiveRequestsFilter.doFilter(ActiveRequestsFilter.java:173)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.startup.JiraStartupChecklistFilter.doFilter(JiraStartupChecklistFilter.java:75)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.multitenant.servlet.MultiTenantServletFilter.doFilter(MultiTenantServletFilter.java:91)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.atlassian.jira.web.filters.steps.ChainedFilterStepRunner.doFilter(ChainedFilterStepRunner.java:78)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:554)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:864)
    at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
    at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1665)
    at java.lang.Thread.run(Thread.java:662)
Caused by: javax.mail.MessagingException: Exception reading response;
  nested exception is:
    java.net.SocketException: Connection reset
    at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:2210)
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1950)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:642)
    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 com.atlassian.mail.server.impl.SMTPMailServerImpl.send(SMTPMailServerImpl.java:164)
    ... 149 more
Caused by: java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:168)
    at com.sun.mail.util.TraceInputStream.read(TraceInputStream.java:110)
    at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:237)
    at com.sun.mail.util.LineInputStream.readLine(LineInputStream.java:89)
    at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:2188)
    ... 155 more

[Nic Brough -Adaptavist-]

Connection reset usually means that the server cannot be reached, you've given it the wrong credentials or the mail server is not allowing the connection from the JIRA server's address or for that user.