Try this:
Try uninstalling the App and delete the Cisco Videoguard Player folder in C: > Users > Your Username > AppData > Local > Cisco > VideoGuard Player and AppData > LocalLow > Cisco > VideoGuard (delete this) and the Sky Go/Sky folders in App Data > Roaming. These folders and files might be hidden so in windows explorer you need to allow it to show hidden files.
Do a search on your PC and delete anything Sky and Cisco related.
Update Java - download most recent from Java.com and install - makes sure you run the installer until it either completes or tells you that it cannot install. This is due to the Java installer also doing a repair on Java components even if it doesn't completely install.
Restart computer - MUST be restarted for Java to update Windows Registry
Reinstall Sky Go and test