The process of recovering an Exchange public folder can be the cause of a lot of pain as it almost always is a very difficult and painstaking process. However, laid out here is a process that works extremely well if you are using Exchange 2010 SP2. This process does not involve restoring datastores or restoring backups to an isolated environment. It can be performed in place.
- Select a public folder server in your environment that was a replication partner for this public folder.
- Set the following key (Replication Flags) to 0. If the DWORD did not exist, please create it. HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\<servername>\Public- <GUID of Public Store>
- Now restore the public folder using your backup software to the original location.
- Use Outlook to logon to a mailbox that had access to the public folders before they were deleted.
- Copy all the folders you wish to restore to another public folder in the hierarchy. Please note that this is the most important step.
- Once step 5 is complete, ensure that the replica lists show all the replication partners.
- Now, dismount the public folder database, set the replication registry key (path in step2) to 1 and remount the database.
- The folders you just restored will disappear as soon as the replication begins but the ones you copied will remain.
This method saves us the headache of creating an isolated environment but forcing replication to be turned off on one of the partners. Let me know if this method helps you!