From: email@example.com [mailto:firstname.lastname@example.org]
The key to enable Exchange 2007 Legacy Mailbox:
Location : HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Backup Exec For Windows\Backup Exec\Engine\ESE
Create Dword: E2K7_MBOX
Hex Value: 1
Recycle BE services
Tools => BE services => Restart All Services
When backing up the individual mailboxes use GRT backup.
To disk is fastest for backup and restore. Leave at least 2 copes on disk if there is enough space for it.
You can also create a job to disk and then an automatic to tape job.
ONLY do the following if you want to backup using the older MAPI type backup which is very slow:
Go to Tools => Options => Microsoft Exchange => Check the box which states Legacy Mailbox [Not recommended] => Click Ok