Another thing a lot of Win 10 users might not realize and that they might want to ensure is disabled, especially if they (e.g.) manage secure credentials in a file of some sort (by default, it appears to be disabled):
Sorry if this has been posted (probably has) but I found this out through some trial and error.
Right click on your file, go to "open with". Use "choose another app" and locate the app you want for the default app. Open it with that app. Once you've done that, your preferred app will now be in the "open with" menu. NOW you can set it as a default for that file. Not sure why that's a thing, but it works.