SEO Redirecting URLs to lowercase excluding static files

As you may know Google treats different cased URLs as different URL entirely. If they find both cases they will judge this as duplicate content so it is a good idea to redirect requests for a URL containing uppercase to lowercase.

This is made easy with the URL Rewriting Module 2.0. You can use the "Enforce lowercase URLs" template to do most of the work for you.

This will create a pattern match of [A-Z] (as in if there is even one capital in the URL) it will 301 redirect to {ToLower:{URL}} which is fairly obvious what it does.

What about static resources files?

You don't really want these redirects to happen since you don't really want search engines to index them so it takes up needless resource. Also, for my particular set up it fails to send them (some sort of weird, secure + load balanced + redirecting issue).

1. Open the Conditions section of your lowercase redirect rule and click Add...
2. Set Condition input to {URL} (which doesn't look at any querystrings).
3. Set Check if input string to Does Not Match the Pattern
4. Change the Pattern field to one that suits you. I have used ^.+\.(axd|gif|jpg|jpeg|png|css|js|svc|ashx)$ since I do not what files with these extension redirected. You may have more. Or less
5. Ignore case should be checked
6. Click OK and Apply your new rule

Your site should now send www.mysite.com/Home/Index to www.mysite.com/home/index with a permanent 301 redirect and leave www.mysite.com/WebResource.axd alone.