I had the same issue and found out only AFTER buying the software and cable that you can only register the program 2 times. So each time i have re-installed due to a comp crash an upgrade, and most recently a new laptop I have had a VERY hard time to get it registered again. So much infact that I spent a whole day searching and finnaly found a copy of Nissan Datascan and USB converter drivers that does NOT require any registration. Just install it and it works. I found this on a foriegn Skyline forum. If anyone else is interested I can give the link I used. Just let me know.