The new widget is a 404 error checker that basically lists all the times a 404 error page has been crawled on your site, and where it was linked to from. If this list comes up with any useful sites linking to you (or not, as is technically the case here) this should allow you to do one of two things:
- If the linker is linking to a page that no longer exists, make sure there is a 301 on the dead URL to a relevant new page. This will mean that any old links being crawled will pass their benefit on to the new page.
- If the linker is linking to a page that never existed in the first place – perhaps they mis-typed it, or used an incorrect URL structure, contact them (where relevant) and ask them to amend their link.
You can see the list produced by logging in to Webmaster Tools and clicking "Diagnostics". The first list it shows you is "Errors for URLs in Sitemaps (##)". Some of the links shown will likely be internal (in which case, fix them!) and some will be external. If you’re lucky you might even find some gems, as a few of my clients did.
Have a look through the list and see what SEO goodness you can find!Tweet