I am trying to upgrade from 16.3.1 to the latest version. If I 'check for updates' in 16.3.1 and choose to install the latest update I get an error message 

'It was not possible to install the files on your computer.

Please verify that all programs are closed and restart the update.'

No programs are open.

I also downloaded the latest version from the websitex5.com. The size is 154818kb. However when I click on it the system hangs straight away.

Any ideas please.