G
Gary VanderMolen
Chances are, it's not you. 
The auto-complete feature in Windows Mail is very limited.
It will only auto-complete for the last 29 recipients you've sent
mail to. That list is separate from your contacts list.
Some report success by typing a few letters and then pressing Tab.
It supposedly auto-fills the rest from your contacts then.
Incidentally, auto-complete works perfectly in the newer Windows
Live Mail, to which you are welcome to upgrade:
http://get.live.com/wlmail/overview

The auto-complete feature in Windows Mail is very limited.
It will only auto-complete for the last 29 recipients you've sent
mail to. That list is separate from your contacts list.
Some report success by typing a few letters and then pressing Tab.
It supposedly auto-fills the rest from your contacts then.
Incidentally, auto-complete works perfectly in the newer Windows
Live Mail, to which you are welcome to upgrade:
http://get.live.com/wlmail/overview