Have the same problem Win Live Mail under Win Vista... but cannot find a solution either.
Hope you found one meanwhile?
I encountered that the windows live mail 2009 (run on WinXP) will be crashed when I create a new mail. Once I type the initial of the recipient name, let's say type "joh" then it will prompts serveral initial with "John Dave", "John Garcia"..etc within contacts list which just below the recipient box. When the choice is displaying, the crash will occur. Does anyone encounter such problem and any solution for that?