About restoring encrypted SQL databases
SQL 2008 supports Transparent Database Encryption (TDE), which lets you encrypt SQL 2008 databases at the backup set level.
When you back up a database that uses TDE, Microsoft recommends that you back up the certificate keys and encryption keys with the database. If you do not include the certificate keys and encryption keys, you must perform all backup and restore operations within the selected SQL instance.
Backup Exec can redirect the restore of the database data that used TDE only if the certificate keys and encryption keys are applied to the destination instance. If the certificate keys and encryption keys are not applied to the destination instance, an error appears stating that the certificate thumbprint cannot be found.
See your Microsoft SQL 2008 documentation.