I have been playing half life 2 and got to the OUR BENEFACTORS level and started out fine, killed the troops and what not. Then I got to the part where you have to jump over the railing to get to the big generator thing after the catwalk and I found I cannot jump. I checked to keys and the jump button works, i reset the controls and went back and checked if I can jump in earlier parts of the game, but still nothing happens, I cant jump over the rail and i'm stuck, I dont dont even know if you are supposed to jump over it, its the only possible thing i can see. help me.