Google Webmaster Tools is very useful for a number of things, but this article will focus on improving your inbound links and on site Page Rank.

Even the best webmasters sometimes have broken links on their site. Even the best webmasters sometimes move or delete a page without properly 301 redirecting the old URL to a new replacement. It happens all the time, but if the 404 error created by these mistakes is not addressed the website may not be living up to its full potential.

There are a number of tools out there that can help you find broken links, but even if you run one of these tools and correct the broken links, if the broken link is created from an external site, you may never spot them. One very easy way to discover these 404 errors is through Google Webmaster Tools. Here’s what you need to do.

1.) Log into your Google Webmaster Tools account.
2.) On the left hand menu, click “Diagnostics”.
3.) Select “Crawl Errors”.
4.) Select the “Web” Tab. (This normally opens by default).

Now you will be given a list of possible errors. We are going to focus on the “Not Found” link. If you see any figure above a zero, there is some repair work to do. If you have a zero, good job, for now you’re okay and you can go grab a coffee. If you see a one or more, continue.

5.) Next, click on “Not Found”.

Google will display a list of URL’s that it has discovered through links, but wound up reaching a 404 page not found error. For every error URL, there is an opportunity here for you to improve your overall site performance.

6.) The first thing you will want to do is setup a 301 redirect for each of these “Not Found” URL’s, re-directing the page to most relevant live page on your site.

You may think you are done with this step, and effectively this will bring back any lost value from your inbound links, and should help to marginally improve your Page Rank. But to be safe, there are a few more things to take care of.

7.) To the right of each of these URL’s you will see a link under the “Linked From” heading “X Pages”. Click this link.

This will show you all the pages that linked to that now non-existent URL on your site. There are basically two types of links you will find in this list; Internal and external.

For all the internal links, those which are from within your own site, hunt down the broken link on your site and remove or update it. This will solve the problem of Page Rank leak within your site, marginally increasing the Page Rank on the page that had the link.

For the external links you will have to rely on the 301 redirects for the most part, but if you spot any that you have control over, be sure to correct them. These may be directory submissions you have made, or perhaps links from other sites you own. For the sites that you have no control over, the 301 redirect should take care of things, but it may not hurt to contact some of the webmasters and request an update where possible.

And that’s all there is to it. If you discovered just a small handful of Not Found errors, then you may not see any immediate impact from correcting them, however, if you stumbled onto a number of URL’s, or even a single URL with a large number of pages linking to it, correcting the problem may help you to improve your Page Rank and your organic rankings.