I try to setup wni xp in my computer and the setup screen shows me 131Mb from the 500Gb hard disk that is equipped?why my whole hard disk capacity isn`t shown?my hard disk is barnd new sata2 WD 500Gb!

You may have to create additional partitions on the drive to use all of it.

I believe that's the limit on size with Windows XP before the service packs. Are you installing from an older CD?

If you've got no other CD to install from (as long as it's the same edit like OEM or Retail, your Product Key should work with an install CD that has SP1 or SP2 on it), you could isntall it with the old version and then upgrade. You won't be able to add the extra 400GB to the partition (even if you convert to dynamic disks, because it's a system partition), but you can use the rest of the space to create a second partition (like drive D).

Above message sound correct
Right click on My Computer and click manage
Now click on disk management
On the right you will see your drives in square boxes
Right click on the drive that is apparently empty and click format and choose ntfs
You should now have a d:drive with the missing space

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