It seems it can't be done. So maybe the Windows 10 app isn't a program for you.
Many people switched to Mozilla Thunderbird when going from XP to Windows 7, Vista or 8, because they didn't like Windows Mail or Windows Live Mail.
That can import what you need, so seems a viable option for you also.
Kees
I have a pc updated from 7 to 10 and now wish to get rid of my old xp pc. I have copied my folders and contacts from Outlook Express. In W10 Mail I have set up the email system and can log on perfectly and see all the new stuff. I cannot find anyway to import my contacts or folders full of saved emails into W10 Mail. Is there a way to do this or has MS given up on stuff from Outlook Express?

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