Email listener: some mails are processed twice


we set up an email listener to receive small xml orders via mail. The listener works fine. The xml files are transferred to the flow service specified in the mail subject. So most of the time we don’t have any problems. But once in a month or so one of these orders (maybe sometimes some more) is processed twice. And it’s processed simultaneously. The flow service seems to be called two times at the same time. We log every step in the flow service and they occur twice in the logfiles. Sometimes even with the same log index. When this error happens it always happens for the first order of the day. But it doesn’t happen every day. So it’s quite strange.
What could be the reason for this? Do you have any ideas?


It looks like you are receiving the mail twice. Can you ensure, if the mail is received only once by your IS? If there is anything unique in the subject, it might help you to avoid processing duplicate orders, by introducing the logic, to handle duplication.

Unfortunately I can’t ensure that we didn’t receive the mail twice. I can’t check it so I have to believe that it’s sent only once. Even I also thought that this could be the reason for this problem.
And even the subjects are not unique I implemented a logic to handle duplication. So the problem doesn’t occur anymore even it’s not solved yet.