Missign or Corrupt NTOSKRNL

1. Insert and boot from your WindowsXP CD.

2. At the first R=Repair option, press the R key

3. Press the number that corresponds to the correct location for the installation of Windows you want to repair.
Typically this will be #1

4. Change to the drive that has the CD ROM. Then type the following
CD i386
expand ntkrnlmp.ex_ C:\Windows\System32\ntoskrnl.exe

5. Take out the CD ROM and type exit