Like a giant virus, Win10 attacked and installed itself on my system.  After it retreated and Win7 was restored (mostly) Win Live Mail started displaying a message about recovering the mail (database?).  Then suddenly all my mail folders disappeared.  I have periodic backups.  Is there a way to: 

1. restore my WLM mail folders and

2, convert them Outlook2016 folders using an IMAP login instead of POP3?

I say Win7 was mostly restored because while basic function was restored, things like Start/Word/(recent-documents) do not work any more.  Is there a remedy for this other than reloading the OS?  I have legacy apps (Autocad) that cannot be loaded and registered again.