Have a problem...

Before installing Vista, I tought of making a backup on a second internal
hard disk which a bought and installed on the original XP professional
machine, I found myself to be very smart doing this.
Unfortunatly now that Vista is installed on this machine the disk is not
accessible. disk manager says "dynamic disk status invalid"? What can/should
I do to gain control over this disk again? I can convert it to a standard
disk (only option available in disk manager) beause then I will loos the
information it contains.

Thanks in advance.

Peter