[SOLVED] posts not publishing to home page

Hello,

Yesterday, I couldn't access my blog for about half an hour, and since it came back, this error message is on the home page:

"Not Found
Sorry, but you are looking for something that isn't here."

Here is my website: http://ohiocitizen.org/

It has 653 posts, and I don't know why this is happening. Posts can still be viewed by clicking the categories and tags. When I am logged in as admin, I can see the posts, but I can't publish new ones. I have checked the WordPress forums and so far can't find a solution that works.

I've tried:
- switching to the default theme
- re-saving the permalink structure
- deactivating the plug-ins

Nothing has worked so far. Does anyone have any other ideas? Thanks!