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When you delete an email message, a contact, a calendar item, or a task, it's moved to the Deleted Items folder in your mailbox. If you're trying to find a message that was deleted, the Deleted Items folder is the first place to look.
Steps for recovering items from the Deleted Items folder.
Recovering items from the Recoverable Items folder
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Delete an item from the Deleted Items folder.
Empty the Deleted Items folder.
Permanently delete an item by selecting it and pressing Shift+Delete.
Steps for recovering items from the Recoverable Items folder.
Steps for recovering deleted items
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