Since EA shut down its support for BF2 a lot of people is playing on downloaded versions with a generated CD-key or the one they found somewhere on the internet, it works, but doing that might result in 'invalid CD-key' error and many of those generated keys are already banned on the only populated FH2 server. What you can do to play the mod is download BF2 from what ever you are able to download it from, will it be torrents or anything else, but to avoid all invalid CD-key problems, you should use original one instead of the one provided with your downloaded BF2 build. You can try to buy one
here. CD-key is the only thing that really matters to play online.
Also, don't forget to patch up your BF2 with 1.41 and 1.5 patches before you will install FH2. An easy way to do the latter is downloading FH2 launcher, which will download the latest version of FH2 for you automaticaly. You can get it
here.
You can download all the necessary BF2 patches here:
