Did you reboot after uninstalling 7.3.9? I dumped xp off one pc and put 7 on it partly because of the problems from fah. The 7.3.9 would not exit all the way - even after trying to uninstall it there was still a "client"
thread in my task manager that I had to manually end before I could get 7.2.9 to install properly and that pc also would not show the control panel window when I clicked the menu item for it from the systray. I really thinking that version of fah just isnt really compatable with xp...
tm completely end all the clients threads - double check in task manager - then delet the work folder. Then when you restart the client it should start from scratch. If that does not work then you would need to reinstall the client to reset the config settings.