EXCHANGE 2003 recovery

I'm assuming the machine was running Windows. I'm not sure what went wrong with your machine, if it was hardware/software related?? So I can't tell you how to fix that aspect of it. But as far as recovering your domain controller...once you get the machine up and running, you will need to reinstall Windows, and rebuild something called the Active Directory, which makes a server a domain controller. Detailed directions for procedure are here: http://www.petri.co.il/how_to_install_active_directory_on_windows_2003.htm.

I'm not as familiar with the Exchange Server part of your question, but I believe it's just like any other program that's running on your server, so you should just be able to restore all of that info from your backup. But here is a setup guide just in case you have to set it up again. (Which hopefully you will not!) Hope all this helps. Keep us posted!!

Chris

What is it you want to recover from the server? If it was decommissioned was another server installed prior? If so wouldn't all the mailboxes have been moved to the new server?
Does the exchange server still have its original name? Is it still security connected to the domain?
The backup AD should be made into the FSMO AD by siezing all the roles. Use NTDSUtil for this. There are lots of online forums that describe how to sieze the AD roles.
Once your AD machine is running you should be able to marry the client accounts to the exchange server. If mailboxes are still on the Ex server then check user accounts for the mailbox location. If these are still your Ex seerver then you should be able to recover the server.
If you plan to restore an IS database then you will need to place the Ex server store into recovery mode first.
Hope this helps.