Avast Ultimate (Multi-Device) Installation Error

[rudi.h]

Hi,
downloaded avast_security_online.dmg from My Subscriptions page.
Tried to install but get always following error:

Download of virus definitions failed!
The network connection was interrupted.

https://www.dropbox.com/s/5g54p0bcdhjniz5/Avast.png?dl=0

But I have network connection working (Streaming Radio during installation)

Has someone had the same issue?
And an explanation...