(picture is linked to download)
If you find that there is missing information after the migration has completed (or someone in organization suspects this) then you need to access your NTBackup created media and potentially recover data. But Windows Server 2008 no longer has NTbackup; Vista omitted the same thing.
What to do? Download the above nifty utility or go to a Windows 2003 Server or XP workstation you still have access to. With the utility you can keep it all in house at the business network which keeps thing simple.
KISS is a DU-IT best practice.