Instructions
Boot your PC with the "Hitman: Blood Money" disk in the CD/DVD drive. Locate the "Hitman: Blood Money" directory on your computer's "C" drive. During installation, this usually goes in C:\Program Files\Eidos\Hitman Blood Money. You may have designated another location if you opted for a custom install.
Locate the hitmanbloodmoney.ini file within this directory. Open it using Notepad.
Move your cursor to the end of the document and type in "EnableCheats" (without quotes). Save your reformatted version of the file. Close Notepad and boot up the game. You will now be able to cheat.