I'm using a Dell laptop pent. 4 3.0 ghz and use an external drive also and I have been having the same problem. I have had all my windows updates installed and it seem to work until I shut it off and then on the next start up gives me the error message "Serial # doesn't match reg code, reinstall hoster"
This is definitly a huge problem as it renders the program useless and makes it totally unreliable, not so good if you have a room full of people to please.
