Hi sammy, on first you can try to uninstall the hp software and after do that you can download and install CCcleaner, it is a free tool that help you to remove all the brocken or the useless register keys.
Also if you have xp or vista operative system you can try the windows restore system, you can find it at start/allprogram/accessories/utility system/System Restore and chose a date before when you had installed the hp software.
let me know if you resolve your problem
ps:international users can post just on our international sections, of course if you know italian language you can post everywhere in italian language!