Sometimes WordPress has some issues using Permalinks on Windows servers.Most people want to use Permalinks so visitors can find what they are looking for easier and so search engings can also find pages easier. When I came across this issue when working with a client most of the suggestions were “leave the Windows server and use a Linux”. While I do like Linux web servers not everyone can do that and therefore it is not really a fix or work around. I have found two options that work for me. This first one is the easiest but if that doesn’t work try option two.http://infolio-rg.ru
You can usually just change to a custom permalink and type this:
Click the image to see a screen shot. What this does is tell WordPress to use the indes.php file to access the permalink via its post name. As I said that usually works but if not you can try option 2.
This option requires you to add a web.config file. Thanks to globalartwork.com for this easy fix. Just download this file: web.config.txt and remove the .txt and upload it to the root of your WordPress site. Most computers will block you from downloading .config files from the internet so that is why I added the .txt is on the end. You must remove the .txt for the file to work.