Windows could not start because the following file is missing or corrupt lt;windows root 7 / System 321 hal.dll -

how do i reinstall a copy

Insert your windows disk

Boot from a windows bootable disk and try to repair it. Insert the bootable disk amp; restart the machine. Press F8 Select boot from CD ROM when it boots it ll ask whether you want to repair or install windows select repair amp; follow the messages hope this will work