Unable to access VIsta ro XP partition

Hello,

I have three drives which consist of one that has Vista, another with XP and
just recently i installed Windows 7 on the other drive. After installing
Windows 7, and tinkering around with it i decided to get back to Vista to
work on somethings. i went to my BIOS and changed my drive to boot to the
Vista drive, but i would get a message that states to use a drive that is
bootable or insert media to boot from. i reverted back to windows 7 and i
noticed both my XP and Vista drives didn't have a drive letter and wasn't
assessible even after attempting to rescan drives. I then attempted to boot
to my XP drive, but the same message was prompted. Now i'm concerned that the
install must of some how messed with both my OS's and am stuck on getting
them to boot.

Since i had some space on my Vista drive i inserted my Vista installer, and
noticed when given the option to pick a drive/partition to install the OS in
it recognized the drives/names of both my XP and Vista partitions
(Vista=Phatcat XP=Fatcat), which leads me to believe that they are still
there, but for some reason unaccessible. I'd appreciate any leads on how to
get them back.

Regards,

Edgar