You can now modify setupldr.bin of the follwing windows: Windows Server 2003 SP1 Windows XP Professional x64 Edition Windows Server 2003 x64 Edition Windows PE 2005 The setupldr.bin of the above versions is the same and has a checksum check built-in so when you try to modify it you get: "NTLDR is corrupt. The system cannot boot." In order to crack it: open it with your favorite hex editor goto hex address: 0x2060 change "74 03" to "EB 1A" save it I also uploaded it for your convenience a