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A FolderClosedException (FCE) is caused when the connection between Jira and the inbound Mail server is closed abruptly by the mail server whilst mail is being retrieved. JEMH is not responsible for the mail connection, which is handled by Jira.
Typically FCEs are caused by too many concurrent logins via multiple inbound mail server configurations for the same mailbox, and
Symptoms
Occasionally, emails will fail to be processed due to a FCE, resulting in a stack trace being added to the ‘atlassian-jira-incoming-mail.log’, for more info see:
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