This worked for me.
Make sure you have 128bit VPN update (live update) if it does not show up (because it has already been installed) go into the installed section (not sure exactly what it is called but the hyperlink is on the same page) re-install it, as installing other modules over top can change files (ie5 etc)
Then under DUN, SETTINGS, CONNECTIONS, SECURITY TAB make sure you have require secure connections ticked (or something like that, the middle one)
If all other config is right this should work, worked for me
good luck
miked