Hi, Hello all. I'm a new user of the techspot forum and have this problem. I recently upgraded to a new desktop with a 64 bit dual core processor. I installed the 64 bit version of Windows XP pro. The installation itself went ok, but after installing, when I try to restart the computer, it does not start up. Instead I get this message: <windows root>\system32\ntoskrnl.exe file corrupted or missing please re install from cd. So, I tried to repair using the Windows CD, and after logging in, I did this: Type: Expand d:\i386\ntoskrnl.ex_ C:\Windows\System32. I said yes to overwrite the file, and then pressed <ENTER> to overwrite. The file was replaced. However, again when I tried to start up the computer, i continued to get the same error message. Does any one know how to fix this problem? I tried to reinstall, and also removed the harddrive, replaced it with an older one, and reinstalled windows. Same error message, and same problem. Could it be a hardware problem? Anything else? Would using Vista instead of the 64bit XP work? Any other suggestions?