Setup Crossfire,error!

Hi, i have a big problem with the setup of crossfire.Everytime that i download it from the website,is impossible to open it or delete it!Actually i have 2 personal computers,1 just bought.I want to play with my brother too,that until now is playing with my account (LT),but he is not so good :P For this reason i want to install crossfire on the other pc,NEW ...but when i download the setup ( i've tryed from 3 different mirrors) is always impossible to install the game.

I haven't viruses,and the OS on both computers is Windows Seven.

Please let me know,

Gaetano.

p.s. Sorry for my bad english , i'm italian