You have two choices:  1.  Install Outlook, preferably version 2003 or
later,
under Vista.  Versions 2000 and 2002 will also run under Vista, but with
some
problems.  Windows Mail needs to use part of it to be able to import the
.pst
files which contain the Outlook messages.  Some, but not all, versions of
Microsoft Office include Outlook.

http://us1.trymicrosoftoffice.com/default.aspx?re_ms=oo&culture=en-US

2.  First, import the messages from Outlook into Outlook Express on an older
computer which has both of them installed.  Then, import from Outlook
Express to Windows Mail.

<http://www.askmehelpdesk.com/email/import-dbx-files-outlook-express-windows-mail
-vista-86458.html>

<http://www.vista4beginners.com/Migrate-from-Outlook-Express-to-Windows-Mail>

Bring along the .wab file if you want your old contacts.  After you copy the
files
to a directory on the hard drive of your new computer, make sure the copies
are read-write instead or readonly before you import them into Windows Mail.

If you want your old contacts, and the import didn't bring them in, start
Windows Mail, then click Tools, then Windows Contacts, them Import,
then Windows Address Book File (Outlook Express contacts), then Import,
then find the .wab file and click on it, then click on Close, then close the
contacts window.