Dazed and confused with ntoskrnl.exe


I am trying to set up a dual book with Vista on Drive C and an already loaded copy of XP on drive E.

Everything seems to work fine until I chose to load XP at boot up. I get this error message:

Invalid boot.ini
Windows cannot start because the following file is missing or corrupt:
<windowsroot>\system32\ntoskrnl.exe. Please reinstall a copy of the above file.

I am confused, this file is sitting on drive e: and drive c. I am not sure what I am missing, and help would be appreciated!