Windows often trashes its own drives, and many of the people who come here come for just that reason. Sometimes Knoppix can read the files even when Windows can't, but sometims Windows does such a good job of trashing the drive that even Knoppix can't read the files.
Here are a couple of suggestions for you:
- 1. Test your memory. Put the knoppix disc in the drive, boot it, and enter memtest at the boot prompt (not "knoppix memtest). Let memtest86 run for at least a pass through all of it's tests. I really don't expect that you have a memory failure but occasionally people who come here do and you would be foolish not to test for this first, particularly since you have the memory test right on the Knoppix disc.
2. If the memory is good then it likely is a disc problem. If you can see drive icons for that disk in Knoppix then the hard drive must at least be spinning and the talking to the computer. Unfortunately, if Knoppix can't mount the partition then ithe data may be so corrupted that Knoppix can't read it. However, there is a chance that just the partition table in the master boot record (MBR) is corrupted and, if that is the case, Knoppix can rebuild a correct partition table and restore access to the data. Two tools that can do this are gpart and testdisk. I like gpart more and suggest that you use it. It will require that you read the man page for it (type man gpart at a shell prompt or finf the man page on-line with a Google search) and will require that you use some command line prompts. With gpart you can run a scan of the entitr drive and the program will try to see if it can determine what partition or partitions are out there. If you like what you see you use other command parameters to tell it to actuall write to the disk and repair the MBR. If the damage was only to the partition table, this will recover the disk for you and Knoppix will now be able to mount the partitions. Testdisk can also try to recover the MBR for you. It's more of a "for dummies" tool, and gives you much less control. If ypu are too lazy to read the gpart man page and learn to use a few command switches, the read the man page for testdisk and take a chance on going that route.