Firstly you need to unblock the contact so they appear on the main window page with your list of friends.
In the main window for Messenger, right-click a contact name, and then click Delete Contact.
A dialog box will appear.
If the dialog box has check boxes, follow these instructions:
1. If you also want to completely remove this contact from all Windows Live properties, such as MSN Hotmail, check Remove from Messenger and Hotmail.
2. If you want to block this contact from seeing your online status, or from sending you instant messages, check Also block this contact.
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