Occasionally, you might be greeted with an HTTP 404 page error.
This is nearly always because we're rolling out an update. We try to minimize how often we do this, but we usually roll out updates several times a week. While they only take a few minutes, the site will go down during that time. We're really sorry about that.
The downtime is never longer than 10 minutes. If you've been experiencing this problem for much longer than that, then please submit a support request. If it's a specific page that is giving the problem, please include a link to that page. If the site went down while you were in mid-purchase, don't worry - if the purchase process went through, we can trace it and help put it right for you.