299175 Free trial/evaluation software

I have software that I would like to provide a FREE TRIAL Period of two weeks. IF I have to do 1 month free trial that is OK too. I do not want people to keep signing up for free trials. I need some type of wrapper software or something to prevent repeated free trials from the same computer. I need this ASAP!!! Initially I get their name, mailing address, email address, and IP address. The people can make up different names and email addresses. The IP they can't make up but that is not always constant because some people have dynamic IP's. I looked at one program priced at $99 called Asprotect that I found at [login to view URL] but I was told that it had loopholes. Is there a way to prevent people from repeated free trials? We do not get peoples credit card information upfront, that would reduce the free trials and the possibility of subsequent sales. I know there is not any 100% effective method to prevent repeated free trials but I want to substantially reduce this from happening. The software will be priced at only $19.95 a year, so I am also hoping that people don't want to keep registering all year for free trials just to save $19.95. I don't want to get into a system that emails out to verify if they are registered. The software that we are selling is PC based and can be used by anyone who has Windows 95 or above if that makes a difference to you. With all you smart programmers out there there must be something you can come up with. Thanks Al PS I have used Scriptlance before and the programmer will tell you we pay our bills!!!