2015 Revised
Instructions how to install WinMail to Windows 8 or 10:
~ install Brinks Take Ownership.reg Here
~ Then right click on your W8 'Program Files/Windows Mail' folder, and click Take Ownership.
~ Then right click on your W8 'Program Files/Windows Mail' folder, and Delete it.
~ Then copy/paste your saved *working* Windows 7 'Windows Mail' folder to Windows 8 same.
~ Create a shortcut from the WinMail.exe you just copied - to the Desktop.
~ copy/paste your Windows 7 C:\Windows\System32\msidcrl30.dll file over to Windows 8 same.
~ Download the WinMailEdit.reg (supplied at the bottom of this post) ..and merge it (x86/x64)
~ Then you are done..
~ Start WinMail and she opens immediately..
...from here you setup the Windows Mail client as normal...
Anyway, within minutes I had WinMail start up instantly in each of these OS's below.
Here's the first run screenshots back on Win 8 beta CP, to Win 8.1, to all Windows 10 Preview versions so far.
Screenshots of WinMail on Win8 beta CP to Win 8.1 & Win10 Preview 9841, 10041, 10162, 10240