If proper precautions aren’t taken before launching your site, Google may crawl and index content that you don’t want available for display in search results. This can include secured pages or any other pages that you simply don’t want indexed.
Luckily, there are processes that allow you to have content removed from Google’s index. If you already have a Webmaster Tools account, you can use the Remove URL tool to speed up the process. If you don’t have a Webmaster Tools account, you will need to add a noindex meta tag and wait for Google to crawl your content again. More details are available at Google Webmaster Central.
Before finishing up this task, you need to make sure that additional steps are taken so that your content isn’t re-crawled by Google spiders and indexed again. These steps should be taken before a site is launched, but are often overlooked or unknown to whomever owns the site. You can learn more about this on Google’s help pages.