Is your account the only one on the PC that has admin abilities? If so try going into your pc's settings and set the account type as regular or public. Then attempt the download again.
My dad has an account, in case I get a bad virus and such
You may need to try from his account, as it may be the 'Head' admin on the computer itself. Or, ask him if he would try it out <3
Also, another thing you could try is looking into dis video:
https://www.youtube.com/watch?v=U3QjreQWuKg (https://www.youtube.com/watch?v=U3QjreQWuKg)
Red made this so it may help you out a bit more then what I can explain.
Hope this helps,
~ Whisper