Backup files unavailable

I recently had my XP computer fail. Rather than upgrade the XP system, I chose to purchase a new computer with Win7 installed. I used Ghost to back up my files from the XP syatem. I now would like to recover some of those files and load them onto my Win7 system. I have Norton Ghost installed on my new system and tried to use it to recover files on the backup. When I do, I get a full list of the image backups but they are all listed as unavailable. Do you have any suggestions on how I can accomplish this?