If your computer is on a network that is marshalled by means of a proxy server, click on the “Proxy Settings” button to set the desired proxy settings.
Click on the “Use proxy server” check box to enable the controls on the screen. You can opt to use the default proxy settings and credentials (as set by Internet Explorer) or specify alternative proxy settings.
The server name may be the name of the server on the network or the IP Address.
If you are unsure about this, you will have a network administrator that you must consult.
Click on the “Save” button to complete.
Click "Network settings test" button
Click "Proxy settings"
Tick the boxes as shown below then save.
Check if this will make any difference.
Please let me know how it goes.