Same problem Re: username in use etc.. Installed Instant Accounts V11 as an administrator, now want to access it as a local user but get this message. I can log on as an administrator and gain access, however, this means constantly logging in and out windows and I do not have the administrator password, so have to get our administrator to do this each time - this is not ideal, as you can well imagine! I wondered if it was a permissions issue, but have been given full control as a user and still cannot gain access.