404 errors in wordpress... Pages have never existed so why is google trying to crawl them?

[SamCUK]

I've just logged into webmaster tools and have over 100 404 errors. I'm running wordpress and I recently added child pages to 2 of my categories like so.

www.mydomain.com/category1/lincolnshire

www.mydomain.com/category1/cambridgeshire  etc...

The 404 errors though are for pages or categories I've never created though. I have over 20 root categories but decided to test adding child pages to only two of them. The 404 errors are for www.mydomain.com/category5/cambridgeshire .... It seem that gogle has tried to crawl these pages that don't exist. Can anyone explain what's going on?

When I click 'linked from' in webmaster tools it's showing links from pages on my site that don't exist also.

[ChadEisenhart]

If you are using SEO by Yoast to create your site map there are settings under the SEO -- XML Sitemap. --  then choices on what to exclude.  I would try exclude some of these.

If that is the case and you make the change in Yoast, check your robots.txt file to see if the change in reflected there also.

If you check some other websites robots.txt file you can get an idea of how it should be set up.