Problem with migration from Apache to IIS
You need to translate the Apache server's rewrite rules into their IIS equivalents, in the root web.config.  

For reference, see what is reported in the Windows Download Instructions.


  IIS7: Create/modify web.config file. Drupal distributions come with .htaccess files for *nix use; IIS7 users should convert this file to a web.config file for their site. If you have used the IIS Manager to create a new site, a basic web.config file will exist in your site's root directory.