N24, stop doing that. I know it gets repetitive to keep saying the same solutions to the same problems, but you don't need be mean and possibly scare away the newbies we have gotten with the new release.
That said, please try to run a quick search before making a brand new topic about something. As a courtesy, I will quote a fix for you, but please search next time.
...Actually, I can't find it. My searching skills might need work. Or maybe no one else can find it either and thus we've found the cause of all these topics popping up with no answers because N24 keeps telling people to search for something they can't find.
As to your actual problem, it happened originally because you didn't shut down FH2 properly. When you start the FH2.exe, it moves the original BF2 shaders and renames them "mods/bf2/shaders_client.zip_vanilla". It then moves the FH2-specific shaders in their place. It moves everything back if you shut the game down normally. If you don't shut it down normally (for example, if you use Alt+F4, if your power goes out, sometimes if your game crashes) the files never get moved back. To fix it, you have to manually move and rename the shader files, but I'm not entirely sure how you do this. Hopefully, someone who actually knows what they're talking about will show up and tell you.