How to delete a page that google has indexed.

20 May 10 11:29 am

Did you submit your site to google webmaster central? If yes, you can request the removal of the indexed URL through google webmaster tools. Go to Site configuration > Crawler access, click the Remove URL tab, then click the New removal request button and follow the prompts.
If you did not submit your site to google webmaster central then you can try the public URL removal tool on https://www.google.com/webmasters/tools/removals
When you encounter a '404' Document Not Found error, it means that the page to which the URL points to does not exist (the URL may be incorrect) or no longer exists on the server (the webpage has been deleted).

20 May 10 10:26 pm

Can you see which page is referring the 404?

You get 404 errors when people try to access a page that doesn't exist. Sometimes they click a broken link on your website, but sometimes it might be people trying to type the URL directly into their address bar, or it might be some sort of automated spam thing hitting random pages on your site, or it might be other sites linking to your site with incorrect addresses.

If it's a broken link on your site, then fix up that link.

If it's because you've got a broken URL showing up in the search engines, you can either do what Fara suggested, or learn how to do a 301 redirect from that "nonexistent" page to another page.

If it's just one page showing up once, then I wouldn't worry about it. This is the kind of thing that can end up sucking a whole lot of your time, when it probably isn't even so important.