You cannot recover deleted items when you use Recover Deleted Items in Microsoft Office Outlook 2003. This is the case when the following conditions are true:
You are trying to make a client connection to a computer that is running Microsoft Exchange Server 2003.
You are trying to make a client connection to Exchange Server 2003 by using remote procedure call (RPC) over Hypertext Transfer Protocol (HTTP).
This behavior occurs because Recover Deleted Items is disabled in Outlook 2003 when you use RPC over HTTP.
Add a registry entry to the Outlook client computer before you connect to the Exchange server. To do this, follow these steps:
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
Click Start, click Run, type regedit, and then click OK.
Locate and then click the following registry subkey:
On the Edit menu, point to New, and then click DWORD Value.
Type DumpsterAlwaysOn, and then press ENTER.
Type 1 in the Value data area, click Decimal in the Base area, and then click OK.
Close Registry Editor.
Note After you create the DumpsterAlwaysOn registry entry, you can recover items that were deleted after the registry entry was created. You cannot recover items that were deleted before the DumpsterAlwaysOn registry entry was added.
For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
178630 How to use Exchange Server 5.5 or Exchange 2000 Server to recover items that are not first transferred to the Deleted Items folder in Outlook