如何配置邮件

java.lang.IllegalStateException: cannot find default email account as no accounts have been configured
at org.elasticsearch.watcher.actions.email.service.Accounts.account(Accounts.java:72)
at org.elasticsearch.watcher.actions.email.service.InternalEmailService.send(InternalEmailService.java:73)
at org.elasticsearch.watcher.actions.email.ExecutableEmailAction.execute(ExecutableEmailAction.java:67)
at org.elasticsearch.watcher.actions.ActionWrapper.execute(ActionWrapper.java:106)
at org.elasticsearch.watcher.execution.ExecutionService.executeInner(ExecutionService.java:381)
at org.elasticsearch.watcher.execution.ExecutionService.execute(ExecutionService.java:274)
at org.elasticsearch.watcher.execution.ExecutionService$WatchExecutionTask.run(ExecutionService.java:419)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)