I, too, would recommend Outlook or Thunderbird, and with the recent advent of the legal sale of recycled Office 2016 licenses you can get Office 2016, including Outlook 2016 if you make sure to buy Office 2016 Pro or Pro Plus, for a song on eBay.
That being said, I have WLM 2012 installed on multiple Windows 10 systems, up through and including Version 1809, and have never had an issue. I downloaded the Windows Essentials 2012 full standalone installer about 7 days before it was pulled from the Microsoft download pages. It's on my Google Drive here: [URL=https://drive.google.com/uc?export=download&id=0B98uELZbPFnOSF8xTzhfYnh4WUU]Windows Essentials 2012 Installer - Includes Windows Live Mail 2012, in ZIP format[/URL].
Brian - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong.
~ H.L. Mencken, AKA The Sage of Baltimore