A. Exchange installs most of its configuration data in Active Directory (AD), so if you need to rebuild a failed Exchange server and don't have a good backup, you can actually tell the Exchange installation process to check with AD. It will pull down the old configuration information and use it, with the caveat that the new Exchange server must have the same name as the one it's replacing.

To use the recovery server mode, enter the command from a command prompt, with the Exchange media folder as the current location.

                              setup /m:RecoverServer                              

Note that this will perform an unattended installation of Exchange server. You must have installed all the prerequisites for the Exchange roles and enabled the required services per a normal Exchange 2010 installation.

Once the installation is complete, the server will have all the same roles as before. If the server was previously a mailbox server, you'll need to restore the mailbox databases—mailbox database content isn't stored in AD!

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