-the pc is ok(can run all programs in the windows)
-as many users use this pc,it has some problem about registry/system file and so on.
-so i try to install the fresh copy of windows xp
-i put the cd and boot from it.
the system loads files as usual
-once i press Enter to format(or R),then the system shows some sentences which mean like:
.....cannot setup windows,the disk is not found,press F3 to quit...
-then i go to windows again.i found that some files such that 'ntldr','ntdetect.com' placed in local d: (not in local c: ).i cut that file and place it in local c:..
-now,it shows ntldr is missing(i know how to fix this).the major problem is,why it cannot find hard disk?and how to fix this?

you have to install the SCSI third party drivers (press F6 when prompted). The prompt is shortly after the Boot to Cd press any key prompt. You will need to get the SATA drivers off the motherboard driver CD (make disc program) If you can't do that then you will have to locate the drivers at the manufacturer's website and also the "makedisc" program.

thank u mr lurkswithin...i ll try hard by myself.thanks for helping.

Your welcome..