I am using Windows 7 and Microsoft Silverlight is installed ( and up to date)
Sky Go allowed me to watch live programmes, but only if I used the Mozilla Firefox browser. However, my default browser is Internet Explorer 11, which did not recognise the Silverlight plug-in. Consequently, it repeatedly asked me to install the Silverlight.
The following solution worked for me.
Run Internet Explorer and open the Tools / Internet Options menu
Click on the Security tab and select the Internet zone
Click on Custom level ... and scroll down to ActiveX controls and plug-ins
Disable "allow ActiveX filtering"
Click on OK
Internet Explorer should now recognise the Silverlight plug-in.