The remote server returned an error (403) forbidde

问题:

I'm having trouble downloading the file, here's the link:

http://vsbg023.cda.pl/apple/13801451161599.mp4?st=zFHkNA18rmxan4AvOQWRmw&e=1431286721

(This is just an example)

As soon as the WebClient tries to download it, it raises the exception "The remote server returned an error ( 403 ) forbidden"

I searched in google, I only found this: http://pastebin.com/arU4WtC7

But nothing gives this error, sometimes it starts to download, but only for a while and the program is suspended, even though the file is still downloading.

Maybe someone knows how to fix it?

You can download the code here: http://pastebin.com/w67Rxikh