To recover unknown partition of windows xp/2003

When you are getting the disk read error and when you try to get it ok by bootable cd at that time you find that the drive is showing the unknown format.

In this case simple remove you faulty hard drive and plug into the another system where the operating system is same and format is also same eg. ntfs or fat32.

keep the HDD as secondary and start the system and go to manage-->disk management and click on the damage partition and it will try to recover it automatically and after that you get the unkown to ntfs than restart and chekc the hdd.

you can take backup of your c drive and than replug the hdd to your original system and most probaly it will start properly

And if do not do so than you can repair by bootable ok

In this way you can recover data from the unknown partition also.