I updated from v16 of ubuntu to v8. When I did that all went well.
A lot of things were funky (e.g., there is no pip and it won't let me add one). The best advice so far is to re-install v18 again.
'Software Updater" app runs, but ends up saying "the software on this computer is up-to-date".
How do I get it to reinstall the latest version of Ubuntu over the (somewhat messed up) current OS?
Addendum:
Someone asked for a screenshot. Here is one from another user who had the exact same problem, but none of the suggested fixes fixed it for me:
BTW, the updater does give me a settings button and pages, but none of them are about the install I want to do. They control, for example, what the upgrade and patch methodology (daily, automatic, etc.) do.
