Try following these steps:
To try and fix that you can clear out the contact cache as follows:
- Exit WLMessenger
- Delete the two folders corresponding with your address in the following folders:
Windows XP:
%userprofile%\contacts
%userprofile%\Local Settings\Application Data\Microsoft\Windows Live Contacts
Windows Vista:
%userprofile%\contacts
%localappdata%\Microsoft\Windows Live Contacts
These folders may be hidden so make sure you turn on hidden folders first.
To navigate to these folders Press
+ R on your keyboard, then copy in the links above