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If you’re a filer, be sure that the received messages in your inboxInbox, and the sent messages in your Sent Items folder are moved to these other folders before they reach 120 days old. Messages in the folders you create outside the Inbox or Sent Items folder will not be automatically deleted by Exchange.
Pilers are people who leave all of their received messages in the Inbox and their sent messages in the Sent Items folder. Pilers need to create at least one folder outside their Inbox and Sent Items folders, in which to store their old messages.
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