640GB reported as 127GB - Windows will not run

[JeffandDanuta]

I have a WD 640GB (WD640AACS-00G8B1) that has stopped running Windows XP-Pro. I have removed the drive from the machine and mounted it to an IDE/SATA to USB converter so I can view the drive through a USB port. Windows reports the capacity as 127G. Windows also reported that the NTFS.SYS file was missing or corrupted, so I copied the file from the machine hosting the USB connection onto the WD drive, now the Windows splash screen comes up for a moment, then the machine reboots, this happens over and over. (I have set the boot sequence to boot first from the USB drive -- the problematic WD unit -- and at boot time I can boot to two different instances of Win XP, the one on the USB drive and the one that is resident in the host machine. If I pick the instance of the host machine, then the boot goes properly and I boot to the host's hard drive.) Win XP reports disk Properties as 69.6G Used, and 58.3G Free. I'm missing something on the order of 513GB of drive space.

I need to recover the entire WD drive capacity and hopefully still be able to boot to Win XP when the drive works again.

I have read that the problem might be in the WD drive's internal tables that report the drive capacity. I do not recall that I created a partition on the drive, and no partitions appear when I use the Drive Manager (Open Windows Explorer, right click on My Computer, then click Manage, and click Disk Management under Stroage). I have Disk0, which is the host machine's drive, and Disk1, which is the drive I am having trouble with.

My USB host machine reports the WD 640G drive as working properly, and the files that I can open seem to be okay, although there is at least one specific file that I am interested in but cannot find on the drive. I did a search for filenames, and on extensions, and the file does not come up in the hits. It would appear that I have files that are written on the missing part of the drive. Since the drive will not boot properly, it seems that I may have system files also written on the missing section of the drive.

 

[Boogieman_WD]

Hey there, Jeff and Danuta!

It really sounds like a unfortunate situation. 🙁
Have you experienced any other issues prior to this problem with that HDD?
Basically you won't be able to boot to Windows with that drive when connected to a different computer. Using an HDD with preinstalled Windows on it from a different computer won't work with another system, unless the motherboards of both computers are the same or pretty similar models.
About Disk Management, would you please post a screenshot of what you see there about the 640GB WD drive (you can use imgur.com to upload the image)?
It really sounds like the partition has been corrupted somehow and hopefully the reason for that is not a physical problem with the drive.
Before you try anything else, I'd advise you to backup all of the files which are accessible now and you wish to keep, just to be on the safe side. After that, I'd suggest that you try accessing the HDD via Ubuntu Live USB, to see if its properly recognized and if you can get to your files. If that doesn't help, you could try out data recovery software: http://www.tomshardware.co.uk/forum/id-1644496/lost-data-recovery.html and http://pcsupport.about.com/od/filerecovery/tp/free-file-recovery-programs.htm.

Hope that helps. Please let me know how everything goes.
Boogieman_WD