Hi LUGUY! That's the way I see it! I trust HTG.
I copied and pasted the PowerShell command to reinstall all apps at the bottom of the link, to see what would happen. It went through a lot stuff. I'm not sure what all it did, but every thing looks OK. As always create a system restore point or better yet a back up image of your OS before doing these kind or procedures. I'm not a big fan of having to reinstall all the apps, but that's the way it seems to work. I'm not having any trouble with the w10 mail app. I would do a restart first to see if that fixes your problem.
You have to right click PowerShell and run as administrator to get these commands to work. I'm also not real familiar with PowerShell
Let me know what you decide and if you had any problems. Maybe other members will reply latter!