Hi,
What’s the version of Outlook?
Deleted item retention must be configured on the server. Otherwise, there will be no deleted items
stored in the dumpster available for recovery. By default, the DumpsterAlwaysOn
registry key is set to 1 in Outlook 2007, so all folders are enabled for deleted item recovery. By default, all folders are recoverable on the Exchange server.
In Outlook 2003 and earlier versions, only the
Deleted Items folder is enabled for recovery by default. All folders are recoverable, however, you must enable the ability to see the items in the dumpster. You must use the DumpsterAlwaysOn
registry key to recover hard-deleted items, which are those items that were deleted while holding down the SHIFT key and that were never moved to the
Deleted Items folder.
More information:
How to Recover a Deleted Item
Recover deleted items