Workflow Notifications Status 'FAILED' checking status

1. Check workflow mailer service current status

  sqlplus apps/<apps password>
  select running_processes
    from apps.fnd_concurrent_queues
   where concurrent_queue_name = 'WFMLRSVC';

  Number of running processes should be greater than 0

2. Find current mailer status

 
  sqlplus apps/<apps password>
  select component_status
    from apps.fnd_svc_components
   where component_id = 
        (select component_id
           from apps.fnd_svc_components
          where component_name = 'Workflow Notification Mailer');

  Possible values:
  RUNNING
  STARTING
  STOPPED_ERROR
  DEACTIVATED_USER
  DEACTIVATED_SYSTEM
 
  sqlplus apps/<apps password>
  declare
       p_retcode number;
       p_errbuf varchar2(100);
       m_mailerid fnd_svc_components.component_id%TYPE;
  begin
       -- Find mailer Id
       -----------------
       select component_id
         into m_mailerid
         from fnd_svc_components
        where component_name = 'Workflow Notification Mailer';
       --------------
       -- Start Mailer
       --------------
       fnd_svc_component.start_component(m_mailerid, p_retcode, p_errbuf);
       commit;
  end;
  /

A workflow notification send event (notification email) can fail at several different points, so monitoring it using one method usually is not going to give you a complete picture.Additionally, you have to keep in mind that the process is dynamic, meaning that as transactions are created into the queues they are also mailed out; so a 
count of data is at best only a snapshot of a particular moment in time.

1. Here is a more robust script for monitoring the wf_notifications table:
select message_type, mail_status, count(*) from wf_notifications
where status = 'OPEN'
GROUP BY MESSAGE_TYPE, MAIL_STATUS
messages in 'FAILED' status can be resent using the concurrent request 'resend failed workflow notificaitons'
messages which are OPEN but where mail_status is null have a missing email address for the recipient, but the notification preference is 'send me mail'

2. Some messages like alerts don't get a record in wf_notifications table so you have to watch the WF_NOTIFICATION_OUT queue.

select corr_id, retry_count, msg_state, count(*)
from applsys.aq$wf_notification_out
group by corr_id, msg_state, retry_count
order by count(*) desc;
Messages with a high retry count have been cycling through the queue and are not passed to smtp service.Messages which are 'expired' can be rebuilt using the wfntfqup.sql