Redirected restore of an Exchange 2007 database as a flat file on a separate Exchange 2007 server fails with Unable to attach to a resource.
0xe000848c - Unable to attach to a resource. Make sure that all selected resources exist and are online, and then try again.
A redirected restore to file (on another exchange server) will fail if the storage group the database being restored from does not exist on the new exchange server.
Exchange Server 1
Storage Groups: First Storage Group, Second Storage Group, 3rd Storage Group.
Databases in "3rd Storage Group": database
Exchange Server 2
Storage Groups: First Storage Group & Second Storage Group
If the database from "3rd storage group were restored to file on "Exchange Server 2" the job will fail.
Create the Storage Group the database was originally located in on the new server
Note: The path to the Storage Group can be placed anywhere on the server.