Soluction:
RegOpenKeyEx(HKEY_LOCAL_MACHINE, YourPath, 0, KEY_READ | 0x0100, &hKey);
RegOpenKeyEx(HKEY_LOCAL_MACHINE, YourPath, 0, KEY_READ | 0x0100, &hKey);
0x0100 is KEY_WOW64_64KEY
Refernece:
http://stackoverflow.com/questions/252297/why-is-regopenkeyex-returning-error-code-2-on-vista-64bit
http://msdn.microsoft.com/en-us/library/ms724878%28v=VS.85%29.aspx
http://msdn.microsoft.com/en-us/library/ms724897%28VS.85%29.aspx