foobuilder

It looks like your site has been hacked and is being redirected to a spam site (which just happens to be down at the moment). Here are steps to take to recover from the hacking. Good luck!

Can you see the text when you click over to the HTML/code editor?

WordPress won’t expand the shortcode if you use two sets of brackets instead of one:

[[gallery]] will render as [gallery].

That way you don’t have to worry about switching to the visual editor. Only problem is that you’ll still get two sets of brackets if the plugin that handles that shortcode is disabled. Fortunately there’s a ticket for this and it should be fixed soon.

No plugin can protect you from exploits in other plugins, themes, or your hosting environment. Read through these guidelines to which I would add one thing: use plugins and themes that are popular and actively maintained. More users means more scrutiny, and less chance for exploits to go unnoticed.

It looks like the theme you are trying to use requires the Multibyte String extension for PHP. That extension is not installed with PHP by default and is not something you will be able to install if you use a shared host. If you use a VPS or dedicated host running Linux you should be able to install it with your distro’s package manager.

For now you can remove the theme and WordPress will revert to the default so your site will at least load.