I've seen several answers for earlier versions of windows, but not 10 -- I'm runnning Windows 10.0.17134, if that matters.
It's currently set so that, on double-clicking a BAT file, it opens in Notepad++, so it's clearly something I did inadvertently (probably trying to set a program for editing, as opposed to opening). I've looked in "Settings / Choose default apps by file type" and see that BAT and CMD are both set for Notepad++, but I don't know how to reset it. If I click on the current setting, it allows me to choose Notepad++ (again, I guess) or "find an app in the app store"; after a LONG time searching (I guess) it says there are no results for ".bat". There's nothing about restoring the default.
How can I get this done?