To run these networking commands in a command prompt window
In the search box on the taskbar, type Command prompt, press and hold (or right-click) Command prompt, and then select Run as administrator > Yes.
At the command prompt, run the following commands in the listed order, and then check to see if that fixes your connection problem:
Type netsh winsock reset and press Enter.
Type netsh int ip reset and press Enter.
Type ipconfig /release and press Enter.
Type ipconfig /renew and press Enter.
Type ipconfig /flushdns and press Enter.
I know. I have a feeling my brothers own PC was affected and so I will be around there at the weekend to fix it. People with little technical knowledge or with ready help can have a very difficult time with many areas of technology - unfortunately that is the way of the modern world.