Since i have no idea of whats the problem, i would install a screenshot taker program and to disable the capture screen hotkey of FH.
I know that Fraps can take screenshots, but it does them in BMP format ( big file sizes) , im sure there are better programs to take screenshots, but i dont remember anyone now. Go and search on the internet for a screenshot program.
edit: also try to run FH as administrator, right click on FH icon and click "run as administrator".