Dan, as well as ensuring that the feature is enabled, you need to be aware that the 'autocomplete' list operates from entries previously typed by you.
You don’t mention which software you loaded, however when you re-loaded your software you may have effectively deleted this list and so are now starting from scratch.
As you now type entries in to text boxes (e.g. Google or site search boxes), the list will be gradually reconstructed and the feature will return to its previous state.
Cheers.
(having said that, I’m with nirofo and think autocomplete is a pita)