Original title: Windows 10 with Windows Live Mail

I recently upgraded to Windows 10 (I wish I never had done that!).  Anyways, I currently use Windows Live Mail 2012.  However, I have a lot of email folders stored in a file called MAIL.MSMESSAGE STORE and I cannot open that file nor can I sync them to show up under Windows Live Mail 2012.  I had a lot of folders too!  The file size is about 20MB.  How can I view these folders under Windows Live Mail 2012?  I already tried FILE, IMPORT MESSAGES, WINDOWS LIVE MAIL....however, the MAIL.MSMESSAGESTORE filename does NOT show up when I click on the BROWSE button.  Can ANYONE help me resolve this problem?  Many thanks!  :)