I sent an email to DonS via the only email address on his web site about the error. The only problem was that my clock had not synced with the internet yet and was just under two minutes off. it was that way when i installed the program. It had the error the second time I tried to run it in less than twenty-four hours. If this is a problem with the software, I am not sure that I am willing to pay the same thing that I can pay for another copy of the working program I have on another system. Has anyone else had similar problems on windows7 and win500?