Problem opening default folders- Outlook

I am running XP Pro with Office 2000, when I attempt to open Outlook, I receive an error message "Unable to Open your default email folders, the information store could not be opened". Microsoft Knowledge Base states that my Secur32.dll is missing or damaged. They give a way to repair using System File Checker, but show how to use it if your running Windows 98, not XP. Where do I find this file and how do I replace it, just delete it and drop new file in System 32 folder? Any tips would be great.....