Unable to delete files from "C:\Winnt\system32" folder

Hi all,

I am trying to delete unwanted files from the system directory "C:\Winnt\system32\" folder in Windows NT machine.

I tired using the functions

DeleteFile(LPTSTR lpFileName)

and

SHFILEOPSTRUCT sh;
sh.wFunc  = FO_DELETE;
sh.pFrom=fileName;
SHFileOperation(&sh)

In both the cases, I cannot delete the file but the same function can delete other files in other directories other than system32 folder

Any suggestions on this would be highly appreciated...

Thanx in advance
Deenad