Restoring Exchange Databases to Another Server
If you experience problems when you restore Exchange databases to the original server, or to the server to which you have restored the original server's configuration, you can restore Exchange databases to a different Exchange server. However, restore Exchange databases to a different server only as a last resort. The Exchange server to which you restore Exchange databases must meet specific criteria. For example, Exchange service packs and hotfixes that you install on the server must match those of the server whose Exchange databases you backed up. For more information about how to restore Exchange databases to a different server, see Exchange 2000 Server Database Recovery.
While the above article refers to the recovery of Exchange 2000, the content also applies to Exchange 2003.
For more information about how to restore Exchange 2003 databases to a Recovery Storage Group on different Exchange 2003 server, see the following Microsoft Knowledge Base article.