How to add new language?

Hi everyone,

I've started offering Portuguese as a new source language, and I need to configure my 2017 starter to use this combination. In the past I've deactivated and uninstalled the programme, then reinstalled to reconfigure the languages but I've just done this and the programme reverts to how it was and I don't get the option to configure new languages. This is pretty urgent as I've already lost a project because of this. How can I add Portuguese?