Outlook 2003

Hi,

I move from using Outlook Express to Outlook 2003.

In Express, when I type the first few letters of a recipients name in the
To... field, the whole e-mail address will show up. THe problem is this does
not happen in Outlook 2003. What do I have to do to have the recipients names
automatically come up just by typing the first few letters of there name,
like in express. Please advise. Thanks!