I tested it on my own computer which is XP x64 SP2. Did you restart your computer immediately after running the patcher and did you open regedit before rebooting? It is x64 aware and will patch the 32-bit version under C:\windows\syswow64\ in addition to the 64-bit version under \system32, so this warrants further investigation. I can't remember if I rebooted right away or not. What should I open regedit for though?