Cubase LE 8 Download Help??

I recently purchased the Alesis IO2 Express audio interface via Ebay. It came with an Activation Code. I followed all the directions but when it came to downloaded it, it did not work. I normally use 7 zip which came up with an error. I uninstalled 7zip and tried downloading the Cubase. Nothing happened. I downloaded Winrar and I am gettign another error. Please help? Thanks.