Upgrading XP with Administrator account

> Just a heads up if you are planning on doing an upgrade of an XP machine
> like
> I did where the only active account is administrator. The install went
> along
> just fine but after it completed I was unable to logon to my machine
> because
> Vista apparently locks out the Administrator account if it was activer
> prior
> to install. As this was the only active account on the machine at the
> time, I
> couldn't do anything. You would think that the upgrader/installer could
> detect this condition and prompt you to create a new account just like it
> does during a fresh install. Oh well. Live and learn.