We recently upgraded from Bamboo 5.9.1 to 5.10.3. Since then we have not received any email notifications. I checked the catalina.out file and found:
2016-04-11 11:48:24,095 ERROR [http-nio-8085-exec-23] [EmailService] Failed to send email
com.atlassian.mail.MailException: javax.mail.AuthenticationFailedException: No authentication mechanisms supported by both server and client
at com.atlassian.mail.server.impl.SMTPMailServerImpl.sendWithMessageId(SMTPMailServerImpl.java:214)
at com.atlassian.mail.server.impl.SMTPMailServerImpl.send(SMTPMailServerImpl.java:151)
at com.atlassian.bamboo.mail.EmailService.sendEmailSynchronously(EmailService.java:137)
at com.atlassian.bamboo.mail.BambooMailer.send(BambooMailer.java:84)
at com.atlassian.bamboo.ww2.actions.admin.mail.ConfigureMailServer.testSMTPServer(ConfigureMailServer.java:190)
at com.atlassian.bamboo.ww2.actions.admin.mail.ConfigureMailServer.doEdit(ConfigureMailServer.java:133)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
...etc...
The Stash server which is on the same host is still successfully sending emails.
I have tried No TSL, TSL, no password, password, etc. all to no avail.