One advantage of Windows Live is the ability to import all of your contacts. However you need to make sure your file is the correct format otherwise you will receive the error The file you chose is empty. Please choose another file. Check your header line, you will probably find one of the headers is incorrect.
The file needs to be in a comma seperated format (CSV). Below is a list of all of the fields, however you don't need all of them, just choose the fields you need e.g.
Title,First Name,Last Name,E-mail Address,Home Phone
Full list of Windows Live contacts header fields:
Title
First Name
Middle Name
Last Name
Suffix
Company
Department
Job Title
Business Street
Business City
Business State
Business Postal Code
Business Country
Home Street
Home City
Home State
Home Postal Code
Home Country
Business Fax
Business Phone
Business Phone 2
Callback
Car Phone
Company Main Phone
Home Fax
Home Phone
Home Phone 2
ISDN
Mobile Phone
Other Fax
Other Phone
Pager
Primary Phone
Radio Phone
TTY/TDD Phone
Telex
Account
Anniversary
Assistant's Name
Billing Information
Birthday
Business Address PO Box
Categories
Children
Company Yomi
Directory Server
E-mail Address
E-mail Type
E-mail Display Name
E-mail 2 Address
E-mail 2 Type
E-mail 2 Display Name
E-mail 3 Address
E-mail 3 Type
E-mail 3 Display Name
Gender
Given Yomi
Government ID Number
Hobby
Home Address PO Box
Initials
Internet Free Busy
Keywords
Language
Location
Manager's Name
Mileage
Notes
Office Location
Organizational ID Number
Other Address PO Box
Priority
Private
Profession
Referred By
Sensitivity
Spouse
Surname Yomi
User 1
User 2
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