Just to and a bit more to CraigVs answer
As long as GRT was enabled when you backed up the Exchange data originally, then if you duplicate from tape back to disk it will create an IMG folder in the disk location and if you look inside this folder, the EDB files etc (for Exchange) will be there. Once you have thse files, there are various, non-Backup Exec options/products, that may allow you to access the e-mails (although you will need to do some research)
Newer versions of Backup Exec also have a redirect to PST option and in theory as long as your original backup job was one with GRT enabled you could use this option (as long as you are now using one of the more up to date BE versions and have a supported version of outlook installed somewhere that our remote agent service is running on.) Note: As we limit testing to more recent versions, we will not have officially tested a redirect to PST restore where the version that did the backup is from some time ago so this may not work but could be worth a try.
Apart from the redirect to PST option Backup Exec has always been designed to recover Exchange data into the same version of Exchange (in fact the same version part is an MS limitation not ours), hence the option of perhaps using the IMG folder content is not something we can advise on with regards to methods once you have the EDB etc files on disk.
