This article explains how to save your Windows Mail 8 and older contacts to a CSV file in Windows 8 and Windows 8.1.
How to Export Windows Live Mail Contacts in Windows 7
Once you've created a single address book in Windows Mail, you don't have to recreate that same address book, even if you switch email programs or email services. You can export Windows contacts to a file format called CSV (comma-separated values), from which most other email programs and email services can import your contacts. To save your Windows Mail 8 and previous contacts to a CSV file in Windows 8:
From the Windows Mail menu, select Tools > Windows Contacts.
Select Export from the toolbar.
