Frankly, it is a royal PITA! I have installed it and uninstalled it several times, and it just will not retain the registration. The horrible serial number (8 groups of 8 digits!) still will not paste in the box. Right clicking the mouse does zilch. So, it is a tedious chore to copy that stuff. Then, you have to copy the previous serial number as well. Then - press REGISTER and it opens the program. Nice! Cool! But as soon as the program is closed, that registration vanishes and the whole event must be repeated. Fortunately, I creaed the ISO file for bootable rescue disk before closing the program, and I can do what I need to do with it. I think I will simply uninstall TI 12/2009. It is not worth the aggravation. BTW - I have NEVER been able to paste in the serialo number!