Nikon Transfer does not work anymore

I have a Nikkon D-80 camera for a couple of months, since the beginning everything was fine with Nikon Transfer that I unloaded according Nikkon instruction. All of a sudden Nikon Transfer has stopped working.
When I press the Start Transfer button, the program dies. Why?
I tried reload the programm from scratch, turn completely off my computer and restarted the all things again, my computer cannot even identify the problem and ask me to check on-line.
Thanks for your precious help.