Can you open Outlook at all? Was this an account or an identity? I'm not that familiar with Outlook, because the ISP I work for does not support it....but if it is anything like Outlook express....If it was an identity go to file and then go to identities and click on add new identities....

If this was an account go to tools and then accounts and then click on the mail tab. Click on add and then mail and then just follow the wizard.....

Sometimes identities and accounts just get corrupt for no special reason other than that it was a Microsoft product....I hope this helps....