Ntoskrnl is missing or corrupt message when booting XP

Resolution :

Method 1
Boot to Recovery Console
expand x:\i386\ntoskrnl.ex_ y:\windows\system32\ntoskrnl.exe
Exit >> <Enter>
(where x: is the drive letter of the optical drive and y: is the partition on which the operating system(os) is installed)
Note : To know which drive letter is for what type Map >> <Enter>

Method 2
Boot to Recovery Console
bootcfg /rebuild >> <Enter>
When prompted Add installation to boot list? (Yes/No/All), type Y >> <Enter>
When Enter Load Identifier appears, type one of the following that is the operating system >> <Enter>
Windows XP Home Edition for Windows XP Home Edition
Windows XP Professional for Windows XP Professional
Windows XP Media Center for Windows XP Media Center
When Enter OS Load Options appears, type /NoExecute=OptIn /fastdetect >> <Enter>.
Exit >> <Enter>