MS Live Mail – all accounts, contacts, folders disappeared

Running Windows Live Mail on 8.1.  This morning after I restarted laptop to complete Windows and AVG updates, I found that everything in Windows Live Mail had disappeared.  By everything I mean all accounts, all folders except Outbox and Storage folders that I have never used.   All my contacts have also gone.  If expect if I had used other features like Calendar, this information would have disappeared too.  I know I didn't delete them, so they must be somewhere.  Can anyone help me find and restore them?  Nothing unusual happened during updates and restart, there are no error messages from mail client.  Not a new installation, have been running Live Mail on Win 8 then Win 8.1 on this laptop more than a year.