Hello Rob,
Please confirm the following:
> When you are getting the above error message? Is it failing while configuration (when it showa a Green status bar?
>Can you try configuring the CRM 2011 Outlook client on the same system using login information to make sure that's it not just happening with your account?
> Uninstallation of the CRM 2011 Outlook client has already been done by you , can you also make sure that passwords are not cached locally into the system where you are facing the issue
Thanks,
Mohammad