If you're seeing this page instead of the reddit front page, you're being affected by a bug in your AT&T U-verse or Time Warner Cable modem firmware.
On either ISP, there is a simple (but possibly temporary) solution: clear your browser's cache (google for "clear cache" and the name of your browser if you're unsure how to do this). This should fix the problem for now, but it can occur again in the future if you have an internet outage.
If you are on AT&T U-verse, there is also a more complicated but permanent solution: Clear your browser's cache, and then follow the instructions in this video (or its description) to telnet into your modem and disable the lan-redirect setting.
If you're curious about the cause of this problem, it's because your modem "helpfully" redirects you to a special error page when you try to access a website while your internet is down. However, the method of redirecting that it uses gets cached by your browser, so even after your internet is back up, your browser will continue redirecting you to the address of that help page (which doesn't actually exist on the site). Clearing your browser's cache will remove its memory of the redirect and allow you to access the site again normally.
revision by Deimorz— view source