Thousands of licensees did the download already, including me. It takes about 20 minutes if you have a stable and proper connection. In your case

• the connection interrupted
• you did not allow the operating system to proceed with the download (!?!)

By the way, you can use an older Mathematica version (if you have one) to check the check sum of the download mentioned on the download page.

I understand that can happen, uan disconnection or the OS does not allow it, but wonfram for windows if discharged well, try it on LINUX, WINDOWS, with firefox, google chrome, Internet Explorer, in different places in my house, at school, and everything happens the same thing you download for windows but not for linux

Unbelievable awkward! Have you looked into the 1.1 kB snippet you manage to download with a hex editor? What it is? Have you searched for some log files about the connections, ssh protocols, windows systems messages, application errors (it depends from the operating system of course), browser download logs? Have you tried with a friend's computer? Do you have antivirus software, children's protection active? Have you used wire shark on that downloading connection? May be you can have a system administrator in your area having a look for you into this? Have you some strange character sets on your keyboard active? Do you run some local security policies? Do you run security enhanced linux (SE linux)?