windows 7 and windows xp in a dual boot ?

Make sure you don't have any unnecessary devices plugged in - e.g. usb drives.

Otherwise, try fixboot and fixmbr commands from XP disc.

when you shrunk the hard drive did you give it a simple name and do not format it under win7 ,do it when you install xp and format it then

Remove any formatting you made for the XP partition and use the XP CD to create and format the partition during the install.

What is your SATA driver set to in BIOS? If set to AHCI then XP might not work, but if you change it to IDE then Win7 will likely not boot.

Have you had XP on the machine before? What settings have you changed in BIOS for Win7 install.

I formatted the drive but didn't shrink it , i had xp before but i didn't change anything in bios, i will try to format the drive d : under xp cd instalation and see what happens.. Thank's

what do you mean did not shrink it ??? is win 7 on the same drive or are you trying to use another hard drive ??

i have changed something in the disk management and from basic disk it changed into dynamic, how can i reverse it ?

Change a dynamic disk back to a basic disk: Storage Services; Local File Systems

I reverst it back in to basic disk, and i started a new instalation o f win xp, i made a new raw partition with xin xp cd instalation and begin to install the win xp, after the restart the same error appeared. ''disk error occurred. press ctrl alt del to restart. Nothing works ....

are you trying to install to a seperate hard drive or have you partitioned your c drive ,what I did was shrink my c drive ,I then gave it a new simple volume and allocated a name for it . i then put my xp disk in drive and rebooted . then when xp came up I did a full format of the new drive I created and then windows xp installed