Scenario: A user is missing mailbox items because they were accidentally deleted or moved from the mailbox and the user cannot find these missing items in their "Recover Deleted Items" folder accessible in Outlook. (Note: How to access the Recover Deleted Items section in Outlook: Outlook 2010 & Outlook 2007)
Next Step: In Exchange 2010 PowerShell, a administrator can use the New-MailboxExportRequest command to create a PST of the users mailbox. The command will export the contents of the mailbox into a PST, in addition reveal the RecoverableItems folder which is a hidden folder in the mailbox that is not seen by Outlook. This folder may contain the contents of the missing items.
Ex2010 Powershell Commands:
Creating the PST Requests:
New-MailboxExportRequest username -filepath \\Servername\Share\File.pst
This will copy everything from the mailbox and put it in a .PST file that you can open in Outlook.
Monitoring the PST Requests:
-Shows the status of the move requests
Get-MailboxExportRequest | Get-MailboxExportRequestStatistics
-Shows the percentage of completion
You can also attach the |FL shell command to existing command it will show all of the available information attached to the move requests.
After the PST request completes:
Once the PST is finished building, you can open it up in Outlook and try to find the missing mailbox items in the recoverable items folders. If you cannot find the missing items, its possible a restore will need to be performed from backup in order to find the missing data.