How do I Import/Convert abook.mab to Windows Live Mail?

I have a new computer with Windows 7 and Windows Live Mail set up. I uploaded my abook.mab file from a previous computer onto the desktop. Window doesn't recognize this extension. Someone suggested that this type of file had to be converted to .csv format for Windows Mail to import it. How do I convert .mab to .csv? Or is there another way?

 

Thanks for your help, Steve. My problem is solved...for the most part. I downloaded and set up Mozilla Thunderbird. It retrieved and imported my netscape address book.ldif instantly. It's didn't see my abook.mab file, though, which was in the same folder on the desktop. But that's okay because the address lists are mostly the same (the .mab file is a bit newer).

I decided to keep and use Thunderbird as my main mail program and uninstall Window Live. They say it's better and it certainly is for me. If you have any suggestions for retrieving the .mab file with thunderbird, I would be most grateful. But I'm very happy with the current results. Thanks again for you guidance.