Originally licensed on a different computer

I have clone a hdd to a bigger capacity hdd. (XP Pro SP3). When I try to install Nitro PDF a pop up saying "Originally licensed on a different computer". I could not find this program in this new hdd. I have visit thier site and try to deactivate the old one but failed. In the Licence Manager as they ask to use, what it mean by 'licence number'. When I try to start the new program (nitro pdf pro) it give the same pop up,since I could not open the program is there anyway to solve this problem. Thanks.