New laptop wont connect ton internet?

Its an Hp presario. Ive tried everything...nothing seems to work. we did the troubleshooting, i restored it, i even made sure not to use norton this time. What should i do? when i try to connect it to my wireless, it wont even let me give a password, but all the others do. We have three laptops in the hosue that work. this one is brandnew, and i cant get it to work! please help:(