I'm configuring confluence 6.5.1 with AWS workmail with IMAP. Workmail doesn't support STARTTLS and i guess confluence is enabling this option by default this is way i get this ERROR msg:
An error has occurred with sending the test email:
com.atlassian.mail.MailException: javax.mail.MessagingException: Exception reading response;
nested exception is:
java.net.SocketTimeoutException: Read timed out
at com.atlassian.confluence.jmx.JmxSMTPMailServer.doSendWithMessageIdSupport(JmxSMTPMailServer.java:120)
at com.atlassian.confluence.jmx.JmxSMTPMailServer.send(JmxSMTPMailServer.java:79)
at com.atlassian.confluence.admin.actions.mail.SendTestEmailAction.execute(SendTestEmailAction.java:57)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:168)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)