To anyone running BackupExec2010 with Exchange 2007, I pity you just like I am currently pitying myself.
For a week now I have battling the dreaded 0xe000848c bug – unable to attach to resource. It’s not like this bug is uncommon as a simple google search for it brings up a 867 mentions of it but it doesn’t seem to be too far stretched either.
The scenario will be that you can do a perfect backup every time of your Exchange server using GRT (Granular Recovery Technology) but once you come to restore you get the 0xe000848c error. You will still probably be fine for restoring whole Exchange Storage Groups and Complete Mailboxes.
There are many different articles out there on how to fix this but I have tried them all and still fallen down. From reinstalling, creating a new account which is listed in GAL, admin rights to the local exchange server, the exchange domain groups, system account login, etc.
http://www.symantec.com/connect/forums/completed-status-failed-final-error-0xe000848c-unable-attach-resource#comment-3720291 <– That is of no help.
In the end I learned my lesson, don’t even bother with GRT, it sucks balls and rarely works properly. Instead I created an Exchange RSG (Recovery Storage Group), set up an Information Store restore job redirecting to the RST and recovered the mailbox data with Exmerge.