I run Outlook XP on Win2000. When I click the "To:" button in a new message, I get the following error message:

"The address list could not be displayed. The Contacts folder associated with this address list could not be opened; it may have been removed or deleted, or you do not have permissions. For information on how to remove this folder from the Outlook Address Book, see Microsoft Outlook Help."

This same message is displayed when I chose Tools/Address Book from the Contacts menu.

What steps should I take to fix this?