I've been using Malwarebytes Antimalware with Windows Defender (built-in) for years now, with no incident. Better combination than any commercial product I've had my hands on thus far  

I was doing some servicing on a new Core i3 HP laptop...It came with both AV, and Norton.....I removed both of them and the system improved in speed dramatically. 

I only use Windows Defender tbh. On macOS Malwarebytes as a preventative measure after I do sketchy things on the internet  

Nothing really sketchy on my end here, and in fact, sketchy stuff is kind of what this Atom windows tablet is for. I'm still really irritated when someone messes with my stuff though. The computer is my servant, and it had damn well better remain that way.

As for what was downloaded that led up to this incident, they were Adobe Digital Editions, Calibre, and a plugin to strip the drm of .EPUB files so I can read my books from the Play Store freely on other devices. The plugin itself isn't an executable, so something must've piggybacked on either Adobe Digital Editions, or Calibre (or just flat out exploited something on a webpage). MalwareBytes seems to have detected something as a PUP.Optional.Conduit.

Looks like running AdwCleaner and MalwareBytes killed the adware. HitMan Pro detected nothing of note afterward, besides a bunch of cookies.

Very oddly, that Malware/Adware had switched off the metered data setting as well, which I had verified was On earlier this day as Windows informed me of an Update that was stopped due to being on a metered connection.