New Post: Error running AutoSPInstaller and creating Web App

This looks like the error that you get when you are creating a host-named site collection for your portal web app. When you initially create your farm (and web app), you need to deselect/clear the "Use Host Header" check box for the portal web app. Note, the "Use Host Header" check box will remain selected for the "My Sites" web app. Additionally, use the URL for the actual server name (i.e. "http://win2012spabc123"). Do not use a user friendly URL, as you would for an alternate access mapping. You will use a user friendly URL for a host-named site collection later (after AutoSPInstaller is finished). When AutoSPInstaller is finished creating the web app, you will have a root site collection with the server name for the URL. You use that as a root site collection to support creating host-named site collections. 

Bear in mind, this applies to host-named site collections (NOT host headers). Using host headers means that IIS will handle the request. Using host-named site collections, means that IIS will simply pass the request up to SharePoint to handle it.