I often get an error, usually when I click on 'Send' but sometimes when I close a contact window. The error message says 'The database cannot be opened using the data provided. Check to see if your username and password are correct.'

When that happens, Outlook freezes and I have to close it from the task manager. Sometimes I can just restart Outlook and it will work just fine, other times I have to re-boot. to get Outlook to work.

Anyone know what might be causing this?