Hello HansBons
Hopefully you saved the .exe file when you originally installed Windows Essentials 2012. If you did, you could try searching for it on your computer. My file is called wlsetup-web.exe with a version number of 16.4.3528.331.
If you haven't got it you could try Filehippo. They have a download for Windows Live Mail 16.4.3528.
I understand that this is actually for all the Windows Essentials 2012 programs. You just select the programs you want (Windows Live Mail in this case) when you run the .exe.
Right click - Run as administrator. As with all installations, it is recommended to temporarily suspend your security software while installing trusted software.
Good luck.