Removing Duplicates in Hotmail and Windows Live Mail

Recently I attempted to import contacts into Windows Live Mail (the free email client from Microsoft). I thought the import was unsuccessful, so I re-ran the import tool another three times.
When I finally looked in my contacts list I had four copies of all contacts.

Luckily, you can [sort of] easily remove duplicates using the Hotmail interface.

First, close down Windows Live Mail.
Second, log into hotmail.com and click on Contacts. At the top of the page there will be an option to "Manage" and then "Clean Up Contacts". Click this option and hit "save" to remove the duplicates.

This works great at removing duplicates and combining profiles, but it only does it three contacts at a time! When you have lots of contacts (I have over 1,000), it takes quite a while.... at least it's automated, though.