This is a steps How To Configure Exchange Email Account in Outlook 2007
Example : We will configure it in Windows XP client.

Click Start >> Control Panel >> Mail

You will see a screen like below :

Click Show Profiles and you will see a next screen below :

Click Add button to the next page 

Outlook Web Access (OWA) built in to the Exchange 2007 server shows a "change password" button in the options pane when a user is logged in. It is enabled by default, even if the password change functionality is disabled by default - frightfully clever from Microsoft...

Anyway, it's a small thing to enable it (source: Knowledgebase Article 297121):