Norton Ghost 15: Help restore complete disk image, Recovery Console doesn't see main internal drive

I've been using North Ghost 15 for six months or so. Backing up an internal 1gig hard drive to an external 1gig drive.

The PC had hard drive failure and after repair, the machine works fine. It's an ACER, Desktop, running Windows 7 Pro. It runs fine and boots into the new installation of Windows 7 on the new HD.

I installed Norton Ghost and can see my backups from a few weeks ago, and can move FILES from the external to the internal drive.

However having a problem when using the boot CD to attempt a complete system restore from backup.

The recovery program sees the external HD, but does not see the internal drive, main drive for the PC, configured as drive C as usual.

Any ideas why? And how to resolve?